39results about How to "Change sensitive" patented technology

The invention provides a micro-droplet sensing device and a method using the same to measure refractivity. A single mode fiber forms a taper area through tapering, two ends of the single mode fiber are connected with a wide-spectrum light source and a spectrograph respectively, the taper area is placed in environment liquid, and annular core fiber optical tweezers control a micro-droplet to be close to the taper area; light emitted by the wide-spectrum light source is transmitted in the single mode fiber, is coupled into the micro-droplet by means of an evanescent field when going through the taper area and generates resonance in the mode of an echo wall, transmission light intensity at a resonance wavelength is reduced sharply to form a resonance valley, and the spectrograph is used to collect transmission light for spectrum analysis. The annular core fiber optical tweezers are utilized to control the micro-droplet to enable the same to form a perfect ball cavity, so that the problem that a solid ball echo wall sensor cannot form echo wall resonance due to unsmooth and defective surface of a solid ball is solved, and the micro-droplet is more sensitive to environment changing. The micro-droplet sensing device has wide application in the aspect of environment monitoring.

The invention provides an online evaluation method for the interference effect of an active phased array radar, and the method comprises the steps: firstly building an index system for the evaluationof the interference effect, and obtaining the weight of each layer of index corresponding to the previous layer through employing an analytic hierarchy process; secondly, an interference party comprehensively uses multi-source information such as priori intelligence knowledge, an online reconnaissance result and a real-time auxiliary situation to quantitatively calculate radar threat degree variation under an interference condition from three aspects of state multi-domain perception, priori mode matching and radar index inversion; and finally, the interference party synthesizes calculation results of the three aspects to obtain a total interference effect evaluation value. Qualitative and quantitative evaluation can be carried out on a typical combat scene, detailed steps of interference effect online evaluation are defined, the method is more sensitive to changes of radar threats, the evaluation result is high in credibility, good online realizability is achieved, a basis is providedfor subsequent interference patterns and interference parameter self-adaptive decisions, and an interference machine can occupy an active position in the confrontation process.

The invention provides a method for detecting a current peak position of a switched reluctance motor, and belongs to the field of rotor position detection of switched reluctance motors. According to the method, only the phase current and the phase voltage of the running motor need to be detected, and position sensors and other devices do not need to be additionally arranged. In the control process, when it is detected that the phase current of the motor has a peak value, the phase inductance value of the motor at the moment is calculated through the current and voltage of the motor, the phaseinductance value is multiplied by the ratio coefficient, which is obtained through simulation, of the rotor position and the inductance value of the motor at the rotating speed, and then the rotor position of the motor at the current peak value moment can be calculated. The method has the characteristics that the problem of current peak position fluctuation in the operation process of the motor can be solved, and the detection is sensitive; the problems of large occupied memory and inaccurate data due to the fact that a traditional table look-up method needs to aim at the influence of variousfactors are solved; and the method is more sensitive to different operation parameter changes of the motor and higher in detection precision.

The invention relates to a safe early warning beam structure for a longitudinal-beam-free middle bearing type arch bridge and an early warning method of the structure. A structure of the longitudinal-beam-free middle bearing type arch bridge does not adopt a longitudinal main beam, and when a hanging rod of the arch bridge fractures, beam falling accidents can be caused. The safe early warning beam structure comprises a continuous longitudinal beam consisting of a middle spanning connecting beam, a middle spanning support beam, a side spanning connecting beam and a side spanning support beam, wherein the continuous longitudinal beam extends to a cross beam between ribs, the middle spanning support beam forms a bag hanger on the hanging rod cross beam through the cross beam support beam and the connecting hanging rod, the top surface of the middle spanning connecting beam is provided with a longitudinal semitransparent communicating pipe, the inside of the middle spanning connecting beam is filled with low-volatility lubricating oil, the liquid level height differences of lubricating oil at the two ends of the communicating pipe are observed by the semitransparent communicating pipe, and the monitoring on the deformation of the middle spanning connecting beam is realized. The structure and the method have the advantages that the longitudinal beam basically bears no load in the operation stage, when small probability events such as hanging rod fracture occur, the longitudinal beam starts to take effects, the occurrence of the beam falling accidents is prevented, through the adopted communicating pipe, the deformation condition of the longitudinal beam can be observed, and the feasibility of monitoring the hanging rod safety on the basis of longitudinal beam deformation is improved.

The invention discloses a mask comprising monitored patterns, and a monitoring method. The mask comprises designed patterns and the monitored patterns, wherein the monitored patterns comprise a first pattern, and a plurality of separated second patterns positioned on the two sides of the first pattern; the extension direction of the first pattern is parallel to the arrangement direction of the second patterns positioned on the same side of the first pattern; the first pattern and the second patterns positioned on one side of the first pattern have first key feature dimensions; the first pattern and the second patterns positioned on the other side of the first pattern have second key feature dimensions; and the first key feature dimensions and the second key feature dimensions are the same from top view. The mask in fault can be found effectively in time; the profile appearance and quality of the designed patterns of the mask can be judged; the pattern quality judging reliability of the mask can be improved; and the yield of a semiconductor product can be improved.

The invention provides an optical touch screen. The optical touch screen comprises an optical reflecting plate, a display screen, a detection control circuit and at least one pair of optical transmitting head and optical receiving head, wherein the optical reflecting plate is arranged above the display screen; the optical transmitting head in each pair is arranged on one side of the optical reflecting plate according to an angle at which incident light can be fully reflected inside the optical reflecting plate; the optical receiving head in each pair is arranged on the opposite side of the optical reflecting plate according to an angle at which the incident light can be received; and the detection control circuit is connected with each pair of optical transmitting head and optical receiving head and is used for detecting light change between each pair of optical transmitting head and optical receiving head. The optical touch screen can achieve more sensitive touch detection and improves the touch experience of a user; anti-jamming anti-dust performance of the optical transmitting head and the optical receiving head is effectively improved; and the service life of the optical touch screen is greatly prolonged.

The invention provides a time sequence concept drift detection method and system, a medium and equipment, and the method comprises the steps: carrying out decomposition of an obtained original time sequence signal through employing an empirical mode decomposition method based on extreme value symmetric extension, and obtaining an intrinsic mode component containing the feature information of different time scales of the original signal; performing coarse graining processing on the obtained intrinsic mode component through fuzzy entropy to obtain an intrinsic mode component converted by using the fuzzy entropy; monitoring the intrinsic mode component after fuzzy entropy conversion by adopting a non-parametric statistical process control model based on generalized likelihood ratio test, calculating the maximum degree of freedom of the generalized likelihood ratio test, and comparing the maximum degree of freedom with a preset control threshold to determine whether a mean value, a variance or drifting of the mean value and the variance occurs or not; conceptual drift detection is realized from the perspective of time domain characteristics of different frequencies.

The invention relates to an acceleration detector based on the resonance light tunneling effect and a detection method. According to the acceleration detector, the high-resolution characteristic of the resonance light tunneling effect principle is utilized to measure acceleration, and the acceleration detector is in a novel structure. The acceleration detector based on the resonance light tunneling effect comprises a fixing frame, an elastic cantilever beam and a quality block, wherein an adjustable light source and a photoelectric detector are fixed on the fixing frame. The resonance light tunneling effect is utilized to detect large change amount of transmission intensity (i)T(/i) caused by tiny shift amount change of the quality block, so displacement amount can be acquired through monitoring the light transmission intensity change, and thereby accurate measurement on the micro displacement amount can be realized.

The invention relates to an angular acceleration detector based on a resonant light tunneling effect theory and a detecting method and provides a novel-structure angular acceleration detector for detecting an angular acceleration by virtue of the characteristic of high resolution of a resonant light tunneling effect. The adopted technical scheme is as follows: the angular acceleration detector based on the resonant light tunneling effect comprises an annular fixed frame, elastic cantilever beams, a mass, an adjustable light source and a photoelectric detector. The variable quantity of high transmitted intensity T, caused by variation of weak transfer quantity of the mass, is detected by virtue of the resonant light tunneling effect, and the angular variable quantity is obtained through the change of the monitored light transmitted intensity, so that the micro angular variable quantity is precisely measured.

The invention relates to an optical fiber structure for temperature detection, a manufacturing method and a temperature detection system, and belongs to the technical field of detection. The structure mainly comprises two single-mode optical fibers and a coreless optical fiber arranged between the two single-mode optical fibers. The coreless optical fiber is arranged to be of a structure with the middle thin and the two ends thick, and the coreless optical fiber and the two single-mode optical fibers are coaxial. The two ends of the coreless optical fiber in the length direction are respectively welded with the end parts of the single-mode optical fibers, a capillary quartz tube sleeves the coreless optical fiber, the middle parts of the capillary quartz tube and the coreless optical fiber are filled with polydimethylsiloxane, and two ends of the capillary quartz tube in the length direction are respectively connected with the single-mode optical fibers in a sealing manner.

The invention relates to the technical field of semiconductor devices, in particular to a temperature measurement method based on MOSFET interface trap effects. The method comprises steps: the extremevalue of recombination current generated at a drain when the MOSFET interface trap serves as a recombination center in the current environment is measured; and according to the extreme value of the recombination current, a corresponding temperature value is searched in a current temperature contrast table and is the temperature in the current environment. According to the temperature measurementmethod based on MOSFET interface trap effects, when a PN junction is biased positively and the source of the MOSFET is suspended under effects of the drain voltage Vd, the gate voltage Vg then makes achannel under the gate enter a depletion state, an exp [Vd/Vt] exponential term is added to the recombination current Ir generated at the drain when the MOSFET interface trap serves as the recombination center, the Ir changes more obviously during a process of adopting the gate voltage Vg for scanning, the Ir is thus extremely sensitive to the change of the temperature, the change of the temperature can thus be detected more easily, and the detection range is large.

The embodiment of the invention discloses a dynamic response amplification method and device of an oil immersible power transformer, which are used for solving the technical problem that the reflection of the change of vibrational and mechanical states of bodies such as an iron core, a winding and the like of the transformer as the vibration magnitude of an oil tank wall is relatively small. The dynamic response amplification method of the oil immersible power transformer, which is disclosed by the embodiment of the invention, comprises the following steps: S1: receiving preset magnification times of vibration of the oil tank wall of the transformer and an initial parameter of a dynamic magnification beam of the oil tank wall; S2: making a harmonic response analysis on the dynamic magnification beam of the oil tank wall and calculating a dynamic amplification factor of the dynamic magnification beam of the oil tank wall; S3: judging whether the difference of the dynamic amplification factor and the times meets a preset threshold; if yes, ending amplification; if not, updating the initial parameter of the dynamic magnification beam of the oil tank wall until the difference of the dynamic amplification factor and the times meets the preset threshold.