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33 results about "Symmetric systems" patented technology
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Symmetric system sampling technique for estimating area change by different scale remote sensing data
The present invention relatesto a method for estimating area factor change of surface fealures of crop planted area, forest covered area and urban land-use area, etc. by using remote sensing data with different dimensions as data source and adopting symmetrical system sampling technique. Said invention utilizes remote sensing image with middle and low resolution, such as MODIS and TM to construct sampling basic unit, uses the primary estimate value of area changed dimension as auxiliary variable quantity to make collation, and adopts symmetrical system sampling technique to select sample point with strong representativeness, and utilizes the sample information to calculate the area change of researched object in whole region.
Owner:RENMIN UNIVERSITY OF CHINA
Symmetric NAT traversal for direct communication in P2P networks when some of the routing NATs are symmetric
InactiveUS9497160B1Low costMinimal server interventionData switching by path configurationNAT traversalNon symmetric
Systems, apparatuses and methods are described for facilitating connection between two or more clients across a network that includes network address translators (NATs). In a particular implementation, the techniques include peer-to-peer (P2P) traffic processing and network address translator (NAT) traversal. Low cost data traffic processing techniques with minimal server intervention are disclosed. The techniques can establish direct connections between clients located in private networks behind NATs. In the case where the clients are each behind a symmetric NAT, the connection can be established indirectly via a non-symmetric NAT (used as a relay) which establishes connection with both symmetric NATs using the disclosed direct connection techniques.
Owner:BIT ACTION INC
Symmetric beamline and methods for generating a mass-analyzed ribbon ion beam
InactiveUS6885014B2Conducive to simplificationEasy maintenanceThermometer detailsBeam/ray focussing/reflecting arrangementsBeam trajectoryBand shape
Ion implantation systems and beamlines therefor are disclosed, in which a ribbon beam of a relatively large aspect ratio is mass analyzed and collimated to provide a mass analyzed ribbon beam for use in implanting one or more workpieces. The beamline system comprises two similar magnets, where the first magnet mass analyzes the ribbon beam to provide an intermediate mass analyzed ion beam, and the second magnet collimates the intermediate beam to provide a uniform mass analyzed ribbon beam to an end station. The symmetrical system provides equidistant beam trajectories for ions across the elongated beam width so as to mitigate non-linearities in the beam transport through the system, such that the resultant mass analyzed beam is highly uniform.
Owner:AXCELIS TECHNOLOGIES
Apparatus and method for accurate electronic color capture and reproduction
InactiveUS7053935B2Improve accuracyImproved signal-to-noise ratio performanceTelevision system detailsTelevision system scanning detailsColor imageSpectral response
An electronic color image capture system includes an optical section for separating an input image into its separate color content and directing the separate color content toward an imaging section, which generates a plurality of color image signals from the input image. The spectral responses of the optical section and the imaging section are selected so as to cascade together to provide all-positive, symmetrical system curves modeled upon red, green and blue color matching functions representative of the human visual system. The color matching functions are derived from three monochromatic light sources and contain no more than three positive lobes as well as one or more negative lobes, wherein the areas under the color matching functions determined by (a) summation of all negative lobes and (b) overlap between the green and red color matching functions are minimized. The color image signals are processed with a color correction matrix with coefficients optimized for signal-to-noise performance for producing an output color image exhibiting an accurate color reproduction of the input image.
Owner:INTELLECTUAL VENTURES FUND 83 LLC
High-capacity UPQC and control method thereof
ActiveCN103618310AAchieve controllabilityRealize functionPolyphase network asymmetry elimination/reductionPolyphase network asymmetry reductionOrthogonal coordinatesElectric power system
The invention relates to a UPQC for flexibility power transmission and distribution of a power system, in particular to a high-capacity UPQC and a control method of the high-capacity UPQC. The high-capacity UPQC is applied to the parallel-connection side of the UPQC by using the structure that a secondary side of a multi-winding transformer is connected with an H-bridge convertor. Three phases on the parallel-connection side are equivalent to three single-phase rectifier models connected to line voltage in a cross mode. As being controlled independently, each H-bridge rectifier is not affected by unbalance of three-phase voltage, and the stability of voltage across the direct current side of the UPQC when network voltage fluctuates is facilitated. A control method based on virtual orthogonal coordinate conversion is adopted, the single-phase rectifier models on the parallel-connection side of the UPQC are equivalent to a three-phase rectifier model, the functions of the controllable power factor and harmonic suppression of a three-phase rectifier are achieved, and all functions of the three-phase rectifier on the condition of the symmetric system voltage can be completely achieved.
Owner:STATE GRID CORP OF CHINA +1
Multi-telescope optical synthetic aperture imaging system and design method thereof
The invention aims to provide a multi-telescope optical synthetic aperture imaging system and a design method thereof in order to solve the problems that the conventional single large-aperture optical system is difficult to process and manufacture, and that the synthetic aperture imaging system cannot reach a desired system index in practice. The designed three-sub-telescope refractive and reflective optical synthetic aperture imaging system consists of a light beam synthesis mirror, three afocal sub telescopes which have the same structure and are arranged in a central symmetry manner on the system entrance pupil face, and optical delay lines which respectively correspond to the afocal sub telescopes; the aperture, on the light beam synthesis mirror, of the common circumcircle of the exit pupils of the three afocal sub telescopes meets the requirement of the magnifying power of the afocal sub telescopes; the optical delay lines are arranged on parallel emergent light paths of corresponding refraction systems; each of the optical delay lines consists of two planar reflecting mirrors; and the light beam synthesis mirror is a rotation symmetric system. The multi-telescope optical synthetic aperture imaging system is compact in structure and rational in layout, and lays the foundation for implementation of engineering application of the synthetic aperture imaging technology.
Owner:XI'AN INST OF OPTICS & FINE MECHANICS - CHINESE ACAD OF SCI
Space laser communication motion double-terminal long distance transmission analog device
InactiveCN1658539AFree-space transmissionTransmission monitoring/testing/fault-measurement systemsAudio power amplifierLight beam
A stimulant device of space laser communication movement double terminals long-distance transmission. The component is double-channel symmetrical system: the beam lambda 1 of the first detected laser communication terminal emitting wave length pass through orderly the first Fourier lens, the first wave minute lens, the first optical imaging amplifier, the scanning double-face reflectoscope, the first reflectoscope, the second optical imaging amplifier, the second wave minute lens, the second Fourier lens to arrive the second tested laser communication terminal; the beam lambda 2 of the second detected laser communication terminal emitting wave length pass through orderly the second Fourier lens, the second wave minute lens, the third optical imaging amplifier, the scanning double-face reflectoscope, the third reflectoscope, the fourth optical imaging amplifier, the fourth reflectoscope, the first wave minute lens and the first Fourier lens to arrive the first tested laser communication terminal; this device realizes the mutually far-field movement of two tested communication terminals. It can be applied to the capture and scanning tracking of planet laser communication terminal and to the test and validation of communication performance.
Owner:SHANGHAI INST OF OPTICS & FINE MECHANICS CHINESE ACAD OF SCI
Microscope apparatus
A microscope apparatus configured to enlarge entrance pupils while maintaining the rotational symmetry of optical systems of a plurality of optical paths after ejection of light from an objective lens to bring out the performance of the objective lens. A microscope apparatus includes an objective lens having a function of collecting light from the object; and optical paths in which all lens groups are rotational symmetric systems and through which light exited from the objective lens passes, wherein when a sum of maximum diameters of entrance pupils of optical systems forming any two of the optical paths is set as ΣDi, and an axial luminous flux diameter determined from a maximum aperture angle α and a focal distance f of the objective lens is set as Dobj, a condition of the following expression is satisfied, ΣDi>Dobj where Dobj=2·f·sin α.
Owner:NIKON CORP
Multi-scale multi-aperture optical imaging system
The invention discloses a multi-scale multi-aperture optical imaging system. The multi-scale multi-aperture optical imaging system comprises a center optical imaging system and four secondary optical imaging systems having complete identical optical structures, wherein the center optical imaging system is a rotary symmetric system, the optical axis and the system center axis are superposed, the four secondary optical imaging systems are arranged at the back of the center optical imaging system, from the perspective of image cross sections, four optical axes of the secondary optical imaging systems are distributed on tip tops of a rectangle which takes the optical axis of the center optical imaging system as the center, and parallel lights emitted from different perspectives by a target are respectively imaged through the center optical imaging system and the four secondary optical imaging systems on different coordinate points on an image plane of one same detector. Independent multiple target images can be acquired by applying the multi-scale multi-aperture optical imaging system to acquire target object information, the center image resolution is higher than the secondary image resolution, images respectively have certain pixels superposed in the field of view, and the multi-scale multi-aperture optical imaging system can provide excellent support for subsequent data processing.
Owner:HARBIN INST OF TECH
Symmetric beamline and methods for generating a mass-analyzed ribbon ion beam
InactiveCN1672235AUniform transport lossShipping Loss ImpactSemiconductor/solid-state device manufacturingIon beam tubesBeam trajectoryBand shape
Owner:AXCELIS TECHNOLOGIES
Control method for asymmetric electric-hydraulic proportional system based on model transferring
ActiveCN104847715AUnanimous responseTroubleshoot consistent responsesFluid-pressure actuator testingServomotor componentsLinear regionMathematical model
The invention discloses a control method for an asymmetric electric-hydraulic proportional system based on model transferring. By converting a transfer function, an asymmetric mathematical model of the asymmetric electric-hydraulic proportional system is converted into a symmetric system model, the symmetry of a load flow model is achieved, and when a unified controller is adopted, responses of forward and reverse motions are identical; by means of signal conversion, the load flow model of the asymmetric system is established, and the purposes of transfer function converting and model converting are achieved, and a new established system model serves as a symmetric load flow model. The achieving method comprises the steps that a reference signal symmetrical to a proportional valve is given, after a signal is converted, a new input signal of the proportional valve is obtained, and proportional valve is controlled to work, so that load flows of the asymmetric electric-hydraulic proportional system in a proportional valve linear region in the forward motion and the reverse motion is identical; by means of the method, an asymmetric effect is eliminated by an asymmetric factor of the system through mathematical conversion, and the identical response of the asymmetric electric-hydraulic proportional system is achieved simply and intelligently.
Owner:CENT SOUTH UNIV
Game map mirror symmetry method and system
The invention discloses a game map mirror symmetry method which comprises the steps of before a camera module renders, turning over the position of a camera to the left lower corner of a game map, multiplying a world transfer camera matrix by a mirror image matrix, and starting reversal removal of a bottom-layer graphical interface; rendering through the camera module, resetting the world transfercamera matrix after accomplishing rendering, resetting the position of the camera, and closing the reversal removal; modifying an X-axis forward direction of a virtual joystick into an X-axis reversedirection corresponding to a game character; and modifying a Y-axis forward direction of the virtual joystick into a Z-axis reverse direction corresponding to the game character. In addition, the invention further discloses a game map mirror symmetry system. By adopting the game map mirror symmetry method and the game map mirror symmetry system provided by the invention, the visual angles of bothgame parties can be completely ensured to be consistent, and the game balance problem brought by a visual angle difference cannot occur, and the problem that the game players disagree path selectionof a game map cannot exist.
Owner:GUANGZHOU YINHAN TECH CO LTD
Synthetic PT symmetric system realized based on passive single resonance coil
InactiveCN112018904ASimplified symmetry conditionSmall footprintCircuit arrangementsCapacitanceCapacitive coupling
The invention relates to a synthetic PT symmetric system realized based on a passive single resonance coil. The synthetic PT symmetric system comprises a first resonance unit, a first lumped unit anda first scattering capacitor, wherein the first resonance unit and the first lumped unit are electrically connected through the first scattering capacitor, and the capacitive coupling of the first lumped unit is equivalent to the capacitive coupling of the first resonance unit. According to the invention, traditional inductive coupling is replaced by capacitive coupling, and an inductive coil witha relatively large volume is replaced by a capacitor with a relatively small volume, so that the space occupied by the whole system is saved, adaptive parameter adjustment of the system is facilitated, and PT symmetry conditions are simplified; and a new thought is provided for exploring non-Hermite physical characteristics in the field of electronics by researching a synthetic PT symmetric system.
Owner:TONGJI UNIV
Non-plug-in shaft torque measuring device
InactiveCN101639392ASimple structureCompact structureWork measurementTorque measurementElectrical resistance and conductanceEngineering
The invention relates to a non-plug-in shaft torque measuring device which is formed by the combination of two semicircular main measuring arms, two auxiliary measuring arms, two main conducting rings, two auxiliary conducting rings and four pressure rings. Two ends of a measuring disc are affixed to the outer surfaces at the joints of the inner edges inside the two main measuring arms, and the measuring disc is affixed on a strain disc. The measuring device has the advantages of simple structure and convenient installation. Because of the semicircular structure of each component, the non-plug-in measurement of a shaft torque can be realized without disconnecting the installation structure of a measured shaft and changing the installation state of a measured system, and the accuracy of themeasurement can be improved. The structure is compact after the components are installed, and the annular symmetric system has little effect on the quality eccentricity of the measured shaft, therebysimilarly improving the accuracy of the measurement. The strain disc is affixed to the measuring disc to perform the measurement, only one resistance strain disc is needed to realize the measurementand can be used repeatedly, thus the cost is reduced.
Owner:中国船舶重工集团公司第七〇二研究所
Two-way protection method of symmetrical system of GFP (Generic Framing Procedure) frame mapping encapsulation business
ActiveCN103209021AAvoid deadlockAvoid oscillationTransmission monitoring/testing/fault-measurement systemsFiberClient-side
A two-way protection method of a symmetrical system of a GFP (Generic Framing Procedure) frame mapping encapsulation business relates to the filed of GFP-F (Frame-mapped Generic Framing Procedure) encapsulation businesses. The two-way protection method comprises step 1, defining different code patterns according to different alarms to enable every alarm to be corresponding to two laser state types and namely the alarms to trigger an open mode and an off mode of a laser; step 2, judging whether switching of a main link and a standby link occurs or not, checking a laser state type of a home terminal client side after a home terminal electric port side receives an alarm code pattern if yes and performing comparison with a current laser state type and updating the state type to a state type which is corresponding to a high priority alarm if the laser state type is an off state type; step 3, determining whether the home terminal electric port side sends the code patterns which are corresponding to the alarms to an electric port of other side or not through the current laser state type; and step 4, utilizing different ways to achieve protection switching. The two-way protection method of the symmetrical system of the GFP frame mapping encapsulation business has the advantages of being capable of effectively achieving corresponding operation, achieving the protection switching and avoiding falling into a thinking or shocking state when fiber-cut of nodes occurs in the links.
Owner:FENGHUO COMM SCI & TECH CO LTD
Symmetric control method for asymmetric hydraulic system based on output feedback
ActiveCN109139616ASimple control strategySimple on-site adjustmentFluid-pressure actuator componentsHydraulic cylinderNon symmetric
The invention discloses a symmetric control method for an asymmetric hydraulic system based on output feedback. The symmetric control method comprises the following steps that a, a state space mathematical model of the asymmetric hydraulic system is established through a load flow linearization equation of the hydraulic system, a flow equation of a working cavity of a hydraulic cylinder and a force balance equation of a valve-controlled cylinder piston; b, starting from the state space mathematical model, dynamic compensation control based on output feedback is conducted on the asymmetric hydraulic system, and thus the asymmetric hydraulic system is converted into a state space symmetric system; and c, unified PID control is conducted on the converted state space symmetric system. According to the symmetric control method, the problems of the large debugging amount and the narrow control range of an asymmetric controller of an asymmetric system for a long time are solved; control strategies are simplified, field adjustment is easier, an operator grasps system debugging more easily, and universality is better; and the reliability and the response characteristics of the system are greatly improved.
Owner:CENT SOUTH UNIV
Microscope apparatus having optical systems forming optical paths parallel to an optical axis of an objective lens
A microscope apparatus configured to enlarge entrance pupils while maintaining the rotational symmetry of optical systems of a plurality of optical paths after ejection of light from an objective lens to bring out the performance of the objective lens. A microscope apparatus includes an objective lens having a function of collecting light from the object; and optical paths in which all lens groups are rotational symmetric systems and through which light exited from the objective lens passes, wherein when a sum of maximum diameters of entrance pupils of optical systems forming any two of the optical paths is set as ΣDi, and an axial luminous flux diameter determined from a maximum aperture angle α and a focal distance f of the objective lens is set as Dobj, a condition of the following expression is satisfied, ΣDi>Dobj where Dobj=2·f·sin α.
Owner:NIKON CORP
Efficient fluidic spray and other delivery multipurpose asymmetrical or symmetrical systems
Efficient fluidic trigger spray and push down delivery multipurpose asymmetrical or symmetrical systems are being described for delivering a multitude of chemical solutions such as any carpet, household, window, glass cleaner, degreasers, health and beauty products, some low viscosity fluids such as cooking sprays, and outdoor / indoor agricultural solutions just to name a few. Both symmetrical and asymmetrical delivery systems can be manufactured using any geometric shape and any base configuration. The efficiency arises from the fact that a protrusion chamber is created in one or more sides of the container and extending a flexible suction tube to communicate with the fluid contained in the protrusion chamber. Thus almost all of the fluid in the container will be delivered regardless of the position the container is operated. Hence, this invention provides means to deliver fluid from the container when the container is operated parallel to the floor, all the way to the upright position and continuing to the position parallel to the ceiling.
Owner:LYLES ANNMARIE ABU JUDOM
A Control Method of Asymmetric Electro-hydraulic Proportional System Based on Model Transformation
ActiveCN104847715BUnanimous responseTroubleshoot consistent responsesFluid-pressure actuator testingServomotor componentsLinear regionMathematical model
Owner:CENT SOUTH UNIV
Large-field unit-magnification catadioptric projection system
A unit magnification projection optical system includes, listed in order along a system axis, a mirror, a lens group having negative power and a lens group having positive power. The optical system is a symmetric system, with an object plane on one side of the system axis and an object plane on an opposite side of the system axis. The object and image planes are spaced apart from the positive lens group by a working distance greater than 100 millimeters.
Owner:COHERENT INC
Code-controlled data encryption method for variability key
The invention discloses a code-controlled data encryption method for a variability key, and relates to an information electronic technology. The invention mainly provides a data encryption method fora non-fixed secret key, and the core of the method is the transformation of'a clear key + a dark key-a variable key '. According to the method, a dynamic'private key 'and a static'dark key' are introduced and are decomposed into a'control code 'and a'controlled code' after being mixed, and then repeated'code control transformation 'is performed to form a'variability key'. And then encryption is carried out through a variability key. The technology of the invention is an unfixed secret key system with an unfixed secret key, which is created outside the existing fixed secret key system. A thirdsystem, namely a double-key symmetric system, is invented and created outside two existing systems, namely a single-key symmetric system and a double-key asymmetric system. Because the repeated transformation is discrete and agreed, the method is more suitable for the implementation of software and the use of an embedded chip. The technology is simple, convenient, feasible, safe and reliable, andcan be widely applied to the fields of national defense, finance, Internet, daily life and the like.
Owner:陈麟华
ARM (Advanced RISC Machine) embedded microprocessor based reactive power compensation device
InactiveCN103532154ARealize continuous adjustmentWill not cause overfillingReactive power adjustment/elimination/compensationReactive power compensationSoft switchingPower factor
An ARM embedded microprocessor based reactive power compensation device comprises a 32-bit microprocessor based on an ARM framework, wherein the 32-bit microprocessor is connected with a 16 MB nonlinear Flash, 8 MB SDEM (software development engineering methodology), IBM (international business machine) linear Flash, an LCD (liquid crystal display), a communication interface, a status signal input DI (digital input) interface, a status signal output DO (digital output) interface and a keyboard. According to the continuous reactive power compensation device which is based on a soft switching technology and suitable for a high-voltage three-phase symmetric system, the continuous adjustment of reactive power can be achieved, a power factor is closer to 1, over compensation cannot be caused, and the problem of repeated switching is solved.
Owner:SHAANXI HI-TECH IND CO LTD
Multiscale Multiaperture Optical Imaging System
The invention discloses a multi-scale multi-aperture optical imaging system. The multi-scale multi-aperture optical imaging system comprises a center optical imaging system and four secondary optical imaging systems having complete identical optical structures, wherein the center optical imaging system is a rotary symmetric system, the optical axis and the system center axis are superposed, the four secondary optical imaging systems are arranged at the back of the center optical imaging system, from the perspective of image cross sections, four optical axes of the secondary optical imaging systems are distributed on tip tops of a rectangle which takes the optical axis of the center optical imaging system as the center, and parallel lights emitted from different perspectives by a target are respectively imaged through the center optical imaging system and the four secondary optical imaging systems on different coordinate points on an image plane of one same detector. Independent multiple target images can be acquired by applying the multi-scale multi-aperture optical imaging system to acquire target object information, the center image resolution is higher than the secondary image resolution, images respectively have certain pixels superposed in the field of view, and the multi-scale multi-aperture optical imaging system can provide excellent support for subsequent data processing.
Owner:HARBIN INST OF TECH
Five-phase system symmetrical component method
InactiveCN108445391AInitial value is simple and preciseDynamo-electric machine testingSymmetrical componentsEngineering
The present invention discloses a five-phase system symmetrical component method. The method comprises the steps of: employing a linear transformation theory and number theory analysis to decompose afive-phase asymmetric system into five determined five-phase symmetric systems; decomposing a voltage and a current in a multi-phase symmetric circuit into symmetrical components so as to prove that each sequence of symmetrical components has independent property, namely, a certain sequence of currents only can cause a certain sequence of voltage drops, and there is no influence for other sequences of electric quantities; because each sequence of reactance in the motor is determined by the property of magnetic flux established by the sequence of currents, in order to show the property of eachsequence of reactance of a five-phase asynchronous motor, decomposing each-phase pulse vibration magnetic flux into two magnetic fluxes with opposite directions, and performing overlapping to allow the properties of the magnetic fluxes to determine the property of the reactance; and finally, obtaining each sequence of reactance through calculation or through corresponding experiments. The five-phase system symmetrical component method is an effective method for solving five-phase motor default phases and symmetrical short circuit, and is simple and accurate for calculation of initial values ofsteady-state transient short circuit current alternating current fundamental components.
Owner:HARBIN UNIV OF SCI & TECH
Symmetrical Control Method of Asymmetrical Hydraulic System Based on Output Feedback
ActiveCN109139616BSimple control strategySimple on-site adjustmentFluid-pressure actuator componentsHydraulic cylinderNon symmetric
Owner:CENT SOUTH UNIV
CrystalSym process
The CrystalSym process is a logical process. It enables users of the process to easily construct symmetric systems of objects within a 3D virtual space. This process utilizes the gamut of the crystallographic 3D space filling symmetry groups of which there are 230, as well as subgroups of these 230 groups. These subgroups include point groups, line groups, frieze groups, plane groups, rod groups and layer groups. It also utilizes a certain class of non-space filling point groups.
Owner:BROKAW HAROLD EDWARD +1
PT symmetric SS topology MC-WPT system and implementation method thereof
ActiveCN113013994AGuaranteed normal transmissionImprove transmission distanceCircuit arrangementsSoftware engineeringTrunking
Owner:CHINA UNIV OF MINING & TECH
Instantaneous value variation distance protection method and system based on coordinate transformation
ActiveCN113075499AIncrease the action speed of distance protectionFast actionFault location by conductor typesControl engineeringControl theory
The invention discloses an instantaneous value variation distance protection method and system based on coordinate transformation, and belongs to the field of power system relay protection. According to the invention, a key technical means of coordinate change is introduced, and an alternating current quantity is converted into a direct current quantity through coordinate transformation. The introduced coordinate transformation is only suitable for a three-phase symmetric system, if the coordinate transformation is directly used, the coordinate transformation is only suitable for a three-phase symmetric fault in a power system, in order to deal with a single-phase earth fault, an interphase short-circuit earth fault and an interphase fault, a virtual three-phase system is constructed based on single-phase information, and different types of faults in the power system are dealt with. According to the method, whether the internal fault occurs or not is determined by comparing the variable quantity of the voltage instantaneous value at the setting point and the variable quantity of the voltage instantaneous value at the fault point, power frequency phasors do not need to be extracted, the action speed is higher, the criterion is simple, the required data window is short, the distance protection action speed of the alternating-current line can be effectively increased, and the safety and stability of the system are improved.
Owner:HUAZHONG UNIV OF SCI & TECH
Complex equipment repair level and spare part inventory configuration combined optimization method
PendingCN113379114AIn line with engineering practiceImprove applicabilityForecastingDesign optimisation/simulationMathematical modelSymmetric systems
The invention provides a complex equipment repair level and spare part inventory configuration combined optimization method, and belongs to the technical field of equipment comprehensive guarantee. The method comprises the following steps: S1, determining calculation parameters of maintenance cost and spare part inventory configuration cost under different repair levels; S2, establishing a joint optimization mathematical model; S3, calculating first-round results of repair level analysis of different stations; S4, carrying out iterative calculation; S5, outputting a final repair level analysis scheme of each station and a corresponding spare part inventory configuration scheme; S6, carrying out validity verification on a joint optimization method; therefore, the joint optimization of the complex equipment repair level and the spare part inventory configuration is completed. According to the method, a calculation result can well accord with engineering practice, the problem that an existing joint optimization method is only suitable for solving a symmetric system is solved, and the method has outstanding substantive features and remarkable progress.
Owner:CHINA ACAD OF LAUNCH VEHICLE TECH
Same-frequency vibration control method for cross-coupling anti-symmetric magnetic suspension rotor system
ActiveCN110045607ASame frequency vibration suppressionApplicableAdaptive controlVibration controlDynamic models
The invention discloses a same-frequency vibration control method for a cross-coupling anti-symmetric magnetic suspension rotor system. The method comprises the following steps of establishing a dynamic model of the cross-coupling anti-symmetric system with same-frequency vibration for the same-frequency vibration caused by rotor mass imbalance in a strong gyro-effect magnetic suspension rotor system, wherein the model is given in the form of a general formula; designing the same-frequency vibration control method based on a cross-decoupling trap, and performing stability analysis on a dual-input dual-output system embedded with a vibration algorithm; converting the dual-input dual-output system into a complex-factor single-input single-output system by complex-factor transformation, and proving the equivalence of the system stability conditions before and after the transformation. The same-frequency vibration control method provided by the invention can be applied to a cross-couplinganti-symmetric system with gyro effect, which can not only effectively suppress the same-frequency vibration caused by the rotor imbalance, but also more easily analyze the stability of the system.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
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