Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

33 results about "Crosstalk interference" patented technology

Crosstalk is a disturbance caused by the electric or magnetic fields of one telecommunication signal affecting a signal in an adjacent circuit. In an telephone circuit, crosstalk can result in your hearing part of a voice conversation from another circuit. The phenomenon that causes crosstalk is called electromagnetic interference (EMI).

High speed connector

The application discloses a high-speed connector, comprising: an insulating body, containing a first terminal group, a second terminal group, a third terminal group and a fourth terminal group, each terminal group is provided with a base, a groove is formed in the base, the groove contains a metal sheet, the base holds a plurality of ground terminals and a plurality of differential terminals, the third terminal group and the fourth terminal group respectively include a sheet structure with plastic material, which is arranged in the groove of the third terminal group and the fourth terminal group, a gap is formed between a plurality of the differential terminals and the sheet structure, and a plurality of the ground terminals and the sheet structure do not have the gap. Therefore, the high-speed connector adjusts the dielectric coefficient of the structure around the terminal, changes the electromagnetic characteristics and crosstalk interference, and improves the quality of high-frequency signal transmission.
Owner:DONGGUAN FUQIANG ELECTRONICS +1

Voice processing method and device, electronic equipment and vehicle

The invention relates to a voice processing method and device, electronic equipment and a vehicle, and belongs to the technical field of voice processing. The method comprises the following steps: acquiring an original voice signal of a target voice area acquired by target voice acquisition equipment; performing echo cancellation on the original voice signal to obtain a first voice signal of the target voice region; performing voice separation on the first voice signal to obtain a second voice signal of the target voice area; and performing noise suppression on the second voice signal to obtain a target voice signal of the target voice region, the noise suppression including echo residual noise suppression and crosstalk noise suppression. Therefore, echo residual noise suppression and crosstalk noise suppression are carried out on the second voice signal at the same time to obtain the target voice signal of the voice region, the method is simple and easy to implement, the calculation complexity is low, the noise suppression efficiency is improved, echo residual and crosstalk interference can be effectively suppressed, the accuracy of voice wake-up and voice recognition can be improved, and the user experience is improved. The method is suitable for an application scene of vehicle-mounted voice processing.
Owner:BEIJING XIAOMI MOBILE SOFTWARE CO LTD +1

Systems and methods for reducing channel crosstalk in fluorescence microscopy.

This specification provides methods and systems for crosstalk reduction, such as removing crosstalk interference from a microscope image signal, in order to reconstruct an intended image from an image signal. In one example, the method includes determining a weighted interference signal of a microscope image by determining a weighting constant of the weighted interference signal that provides minimum variance; removing the weighted interference signal from the whole signal; and determining the intended image signal based on the removal of the weighted interference signal from the whole signal.
Owner:ARACELI BIOSCIENCES INC

Probe performance testing method

PendingCN121578216AElectrical measurementsInterference resistanceCrosstalk interference
The invention relates to the technical field of semiconductor probe performance testing, in particular to a probe performance testing method, which comprises the following steps of: calculating resistance consistency and a signal transmission fidelity ratio of a probe interference working condition through a contact simulation test and a signal transmission simulation test, and performing single-probe simulation verification; for double probes formed by qualified single probes, calculating contact pressure interference variables and electromagnetic crosstalk interference variables, and carrying out cooperative interference judgment; extracting historical probe false data, and constructing an interference false risk model and a non-interference false risk model; grouping the double probes according to interference degrees, and substituting the grouped double probes into corresponding models to calculate risk assessment values; determining an adjustment direction and an adjustment scheme for the high-risk group, and calculating the average attenuation rate of the double probes after adjustment; and after the attenuation rate is verified to reach the standard, the probe group is determined as a qualified performance test probe group, so that the accuracy, the stability and the anti-interference capability of semiconductor probe performance detection are effectively improved.
Owner:JIANGSU JINCHENG SEMICONDUCTOR CO LTD

Wiring terminal and FPC connector comprising same

The utility model relates to the technical field of electric connector manufacturing, in particular to a wiring terminal and an FPC (Flexible Printed Circuit) connector comprising the same. The wiring terminal only retains a signal transmission function, and is composed of an embedding segment, a vertical thrust segment, an elastic top contact conduction segment and a PCB welding segment. And the embedding section and the elastic top contact conduction section are formed by extending the rear side wall of the vertical thrust section backwards. And the PCB welding section is formed by forwards extending the front side wall of the vertical thrust section. Therefore, on one hand, a charge distribution surface is greatly reduced, and the stability and reliability of signal transmission are ensured; in addition, at least one of the wiring terminals is grounded, so that the problems of electromagnetic waves, crosstalk interference and the like which are generated in the signal transmission process are weakened to a certain extent; and on the other hand, when the flexible flat cable is inserted in place relative to the FPC connector, the plurality of wiring terminals are electrically conducted with the flexible flat cable in an elastic pressing contact manner, so that the flexible flat cable is prevented from being quickly worn in long-term application.
Owner:CVILUX TECH SUZHOU

Electrical connector and method of manufacturing the same, and overlying right angle connector assembly and method of assembling the same

ActiveCN116780235BCrosstalk interferenceElectrical connection
The present application provides an electrical connector, a manufacturing method thereof, and an upper layer oblique insertion assembly and an assembly method thereof. The electrical connector and the upper layer oblique insertion assembly can shield the conductive terminals by a bridging shield to reduce signal transmission interference of the conductive terminals and achieve electrical connection between the conductive terminals on the electrical connector, thereby suppressing the generation of coupled crosstalk interference when transmitting high-speed signals. Therefore, the electrical connector and the upper layer oblique insertion assembly of the present application can meet the customized requirements of the electrical connector for transmitting high-speed signals. In addition, the components of the electrical connector of the present application are assembled by oblique insertion, which can reduce the height of the electrical connector and thus reduce the internal space occupied by the electrical connector in the electronic device, so that the electronic device can continue to develop in the direction of lightness, thinness and smallness.
Owner:TARNG YU ENTERPRISE

SYSTEMS AND METHODS FOR REDUCING CHANNEL INTERROGATION IN FLUORESCENCE MICROSCOPY

PendingDE112024000725T5Image enhancementImage analysisFluorescenceCrosstalk interference
This section provides methods and systems for reducing crosstalk, for example, for removing crosstalk interference from a microscope image signal in order to reconstruct an intended image from the image signal. In one example, a method involves determining a weighted interference signal of a microscope image by determining a weighting constant for the weighted interference signal that yields minimal variance, removing the weighted interference signal from the overall signal, and determining the intended image signal based on the removal of the weighted interference signal from the overall signal.
Owner:ARACELI BIOSCIENCES INC

Interlocking structure for crosstalk reduction and method of manufacture

An electronic system having a mounting substrate with a plurality of layers. The mounting substrate combines an upper shield structure and a lower shield structure to form an interlocking shielding structure to reduces crosstalk interference and improve return loss and insertion loss for high-speed serial communication circuits. The upper shield structure and the lower shield structure have a series of grounded reference shields that reduce unwanted electrical signal interferences.
Owner:ASTERA LABS INC

Distributed optical fiber vibration sensing array based on sensitized vibration sensing units, measurement system and use method

PendingCN121954197Ainhibitory positionSuppress crosstalk from irrelevant signalsSubsonic/sonic/ultrasonic wave measurementUsing wave/particle radiation meansCrosstalk interferenceVibration isolation
The invention provides a distributed optical fiber vibration sensing array based on sensitized vibration sensing units, a measurement system and a use method. The sensing array is formed by repeatedly connecting an optical fiber sensitization vibration sensing unit, a vibration insensitive unit and a weak reflection unit according to a specific sequence, the optical fiber sensitization vibration sensing unit improves vibration sensitivity and coupling efficiency through sensitization packaging, and effective capture of weak vibration signals is guaranteed; the vibration insensitive unit realizes vibration isolation between adjacent sensing units and between a non-sensing section and a sensing section; and the weak reflection unit is used for marking the position of the sensing unit and providing a reference for accurate positioning. After the array is connected to a DAS demodulator, the position of the sensing unit is determined through a high-signal-to-noise-ratio reflection signal of the weak reflection unit, and a target position signal is extracted to complete acceleration parameter measurement. According to the invention, crosstalk interference is effectively suppressed, and the accuracy of vibration positioning and acceleration measurement in long-distance monitoring is improved.
Owner:HARBIN ENG UNIV +1

Electric connector

The utility model provides an electric connector, which comprises an insulating seat body and two conductive terminal groups assembled in the insulating seat body, a plurality of signal terminals in the conductive terminal groups are all provided with bases made of insulating materials, and a plurality of grounding terminals are directly punched and formed by a connecting sheet. The butt joint parts of the plurality of grounding terminals are in a reverse folding mode, so that the suspended tail ends are in a relative bending state towards the direction of the butt joint space, the butt joint parts of the plurality of signal terminals are in a relative inclined extending state, and a wrapping rubber base is arranged at the position of the connecting piece. Therefore, the plurality of signal terminals and the plurality of grounding terminals are arranged in a non-coplanar shape, and noise of adjacent signal terminal pairs can be shielded and crosstalk interference between the signal terminals in the same row can be improved through the integral structure design.
Owner:KUNSHAN HONGZHI ELECTRONIC CO LTD

Systems and methods for fluorescence microscopy channel crosstalk mitigation

ActiveUS12487441B2Image enhancementImage analysisMicroscopic imageCrosstalk interference
Methods and system are provided herein for crosstalk mitigation, such as the removal of crosstalk interference from a microscopy image signal to recover an intended image from the image signal. In one example, a method includes accumulating a plurality of weighting constant values and variance data to determine a weighting constant of a weighted interference signal of a microscopy image, wherein determining the weighting constant comprises fitting the plurality of weighting constant values and variance data to a quadratic curve; determining the weighted interference signal of the microscopy image based on the weight constant; removing the weighted interference signal from an overall image signal of the microscopy image; and determining a recovered image signal based on removal of the weighted interference signal from the overall image signal.
Owner:ARACELI BIOSCIENCES INC

Electric connector

The utility model provides an electric connector, which comprises an insulating seat body, a conductive terminal group and an impedance matching element, the conductive terminal group accommodated in the insulating seat body comprises two groups of a plurality of signal terminals and a plurality of grounding terminals which are correspondingly arranged, each two adjacent signal terminals is provided with a base for in-mold injection, and the impedance matching element is arranged on the base. The grounding terminals are provided with bridging parts covering the base at intervals, the impedance matching element is arranged between the two adjacent conductive terminal groups and comprises conductive plastic and a plurality of grounding sheets arranged on the two surfaces of the conductive plastic, and the grounding terminals and the grounding sheets are electrically contacted to form common grounding. Therefore, noise of adjacent signal terminal pairs is shielded, crosstalk interference between signal pairs in the same row is improved, and high-frequency performance is further optimized.
Owner:KUNSHAN HONGZHI ELECTRONIC CO LTD

Electric connector

The utility model relates to the field of electronic devices, in particular to an electric connector, which comprises a shielding shell, an insertion port, an insulating colloid group and a transmission conductor group, the transmission conductor group comprises a first transmission conductor group welding part, two first high-frequency differential transmission conductor pair welding parts, at least one first grounding transmission conductor welding part, a second transmission conductor group welding part and two second high-frequency differential transmission conductor pair welding parts; when a counter electric connector is placed into the shielding shell from the insertion opening and is conducted with the transmission conductor group on the insulating colloid group, the welding part of the first grounding transmission conductor can isolate noise generated by the first high-frequency differential transmission conductor to the welding part, and the advantages of solving the problem of high-frequency crosstalk interference and stabilizing the high-frequency transmission speed are achieved.
Owner:V GENERAL TECH CO LTD

Multi-port signal processing method for distributed small base station and related device

PendingCN121239309ARadio-over-fibreMultimode transmissionCrosstalk interferenceRadio frequency signal
The invention relates to the technical field of wireless communication, in particular to a multi-port signal processing method for a distributed small base station and a related device. The method comprises the following steps: receiving 4GA / B and 5GA / B radio frequency signals of two-way MIMO through an SMA interface, separating a transmitting signal TX and a receiving signal RX by using an FDD duplexer aiming at an FDD signal, and separating the TX and RX signals by using a TDD radio frequency switch aiming at a TDD signal for receiving and transmitting link isolation of signals of different systems. Through a multi-port signal processing architecture, the problems of architecture complexity and cost of a traditional distributed small base station system are effectively solved. Aiming at the signal characteristics of 4G FDD and 5G TDD systems, differentiated transceiving isolation is realized by adopting an FDD duplexer and a TDD radio frequency switch, the link isolation of signals of different systems in a transmitting time slot and a receiving time slot is ensured, crosstalk interference is avoided from a physical layer, and the signal purity is improved.
Owner:TAICANG T&W ELECTRONICS CO LTD

SYSTEMS AND METHODS FOR REDUCING CHANNEL INTERROGATION IN FLUORESCENCE MICROSCOPY

PendingDE112024000746T5Fluorescence/phosphorescenceFluorescenceCrosstalk interference
This section provides methods and systems for suppressing crosstalk, for example, for removing crosstalk interference from a microscope image signal to reconstruct an intended image from the image signal. In one example, a method involves accumulating a multitude of weighting constant values ​​and variance data to determine a weighting constant for a weighted interference signal of a microscope image. Determining the weighting constant includes fitting the multitude of weighting constant values ​​and variance data to a quadratic curve; determining the weighted interference signal of the microscope image based on the weighting constant; removing the weighted interference signal from a composite image signal of the microscope image; and determining a reconstructed image signal based on the removal of the weighted interference signal from the composite image signal.
Owner:ARACELI BIOSCIENCES INC

Plastic and metal composite overturning pressing piece and FPC connector comprising same

The utility model relates to the technical field of manufacturing of electric connectors, in particular to a plastic-metal composite turnover pressing piece and an FPC (Flexible Printed Circuit) connector comprising the plastic-metal composite turnover pressing piece. The metal shell is made of a low-resistance and high-strength material and is grounded. The plastic and metal composite overturning pressing piece is formed by combining a plastic overturning pressing plate and a metal shell. For the plastic turnover pressing plate, the rear side wall of the pressing plate body extends forwards to form an avoiding notch. And the chamfered edge which is elastically pressed by the mechanical terminal and is limited is formed in the avoiding gap under the action of the pressing shaft. The left rotating pivot and the right rotating pivot are formed on the left side wall and the right side wall of the pressing plate body. Therefore, on one hand, the problems of electromagnetic waves, crosstalk interference and the like which are generated in a signal transmission process are weakened; and on the other hand, the stability and the reliability of the locked state of the plastic metal composite overturning pressing piece are ensured, and the design concept of the large-size plastic metal composite overturning pressing piece becomes reality.
Owner:CVILUX TECH SUZHOU

System and method for wireless charging of devices

A charging system is disclosed. The charging system includes multiple charging circuits to simultaneously charge chargeable devices in proximity of the charging system. The charging circuits establish wireless communications associated with charging of the chargeable devices. Due to simultaneous wireless communications, a cross-talk interference leads to an error in at least one of the wireless communications. Upon detecting the error, the corresponding charging circuit generates a delay value. After a time delay that is based on the delay value, the charging circuit reestablishes the wireless communication with the chargeable device thereby mitigating the crosstalk interference. The charging circuit charges the chargeable device upon successful reestablishment of the wireless communication.
Owner:NXP BV

Electrical connector

The application discloses an electric connector, which comprises an insulating body and a plurality of transmission modules. Each transmission module comprises a terminal assembly and a cable assembly. Each terminal assembly comprises two terminals and a shielding shell. Each terminal has a contact portion, a wiring portion and an intermediate portion. The first shielding portion of the shielding shell is arranged outside the wiring portions of the two terminals, and the first shielding portion is provided with an open area exposing the two wiring portions. A conducting tab is electrically connected with the shielding shells of the terminal assemblies in the same row. The conducting tab shields the open areas of the shielding shells in the same row. Each first shielding portion and the conducting tab jointly form a shielding space and are arranged outside the corresponding two wiring portions. The application can provide good shielding for the wiring portions of the terminals and reduce the crosstalk interference on the terminals. Meanwhile, the conducting tab connects the shielding shells in the same row into a whole grounding structure, thereby improving the signal crosstalk.
Owner:LOTES ZHONGSHAN CO LTD

Special structure data cable insulation core wire and preparation method thereof

PendingCN121726166AClimate change adaptationInsulated cablesElectrical conductorCrosstalk interference
The invention discloses a data cable insulated core wire with a special structure and a preparation method thereof, and relates to the technical field of signal transmission, in particular to the prepared data cable insulated core wire with the special structure, the prepared data cable insulated core wire comprises four inner conductors and an insulator, the inner conductors are wrapped by the insulator, and the four inner conductors are arranged in a star shape; in the four inner conductors, the distances between every two non-adjacent inner conductors are the same; and the insulator adopts a micropore structure with uniform and consistent pores. According to the invention, the insulated core wire is prepared by adopting a synchronous integrated extrusion molding technology of the four inner conductors, so that the length of each inner conductor in the insulated core wire is kept consistent, the spacing of the inner conductors is kept stable, a twisting or arranging process after a plurality of conductors are independently insulated in a traditional structure is omitted, the core wire filling coefficient is improved, the outer diameter of a finished product of the data cable is reduced, and the production cost is reduced. And signal delay distortion caused by path difference is effectively suppressed, crosstalk interference and signal transmission attenuation between line pairs are greatly reduced, and the signal transmission quality is improved.
Owner:JIANGSU TONGGUANG ELECTRONIC WIRE & CABLE CO LTD +1

High-speed wire harness comprehensive test method and system based on environmental perception

The invention relates to the technical field of wire harness testing, in particular to a high-speed wire harness comprehensive testing method and system based on environmental perception, and the method comprises the steps: carrying out the electromagnetic vibration threshold value determination operation based on a high-speed wire harness to be tested and an environmental perception module, obtaining an optimal test sampling frequency and an optimal electromagnetic interference intensity threshold value, setting a test host, and carrying out the testing of a high-speed wire harness. Performing signal attenuation test on the high-speed wire harness to be tested to obtain signal test intensity, monitoring the vibration amplitude and the vibration frequency of the high-speed wire harness to be tested in real time, calculating a real attenuation value, performing crosstalk monitoring on the high-speed wire harness to be tested to obtain a real crosstalk interference value set, and performing crosstalk interference on the high-speed wire harness to be tested; and performing joint stability test on the high-speed wire harness to be tested to obtain disconnection times, and completing high-speed wire harness comprehensive test based on environmental perception based on the unqualified high-speed wire harness or the qualified high-speed wire harness. According to the invention, the test efficiency and detection precision of the high-speed wire harness can be improved.
Owner:DINGLI AUTOMATIC TECH CO LTD

Electric connector, electric connector combination and terminal module

A terminal module comprises a differential signal terminal pair, two grounding terminals and an insulating frame. Each grounding terminal is provided with a plate surface; the insulating frame partially wraps the differential signal terminal pair and the two grounding terminals in an integrated mode. The insulating frame is provided with a surface corresponding to the two plate surfaces of the two grounding terminals, and the surface is provided with two concave sections. At least one part of the position of each sunken section corresponds to the plate surface of the corresponding grounding terminal, each sunken section is of a long structure, and the length direction of each sunken section extends in the length direction of the corresponding grounding terminal. Therefore, the two signal terminals can keep good signal integrity performance during signal transmission, and crosstalk interference between two adjacent differential signal terminal pairs can be reduced.
Owner:MOLEX INC

Systems and methods for fluorescence microscopy channel crosstalk mitigation

Methods and system are provided herein for crosstalk mitigation, such as the removal of crosstalk interference from a microscopy image signal to recover an intended image from the image signal. In one example, a method includes determining a weighted interference signal of a microscopy image by determining a weighting constant of the weighted interference signal that provides a minimum variance, removing the weighted interference signal from an overall signal, and determining the intended image signal based on removal of the weighted interference signal from the overall signal.
Owner:ARACELI BIOSCIENCES INC

Structure of stable liquid crystal display module capable of reducing crosstalk interference

A structure of stable liquid crystal display (LCD) module includes at least one data driver for receiving data control signals from a master control unit (MCU) and transmitting data driving signals via a part of data lines to liquid crystal units in the stable LCD module; at least one data switch component for grounding the data lines via capacitors when the data lines do not have the data driving signals; at least one scan driver for receiving scan control signals from the MCU and transmitting scan driving signals via a part of scan lines to the liquid crystal units in the stable LCD module; and at least one scan switch component for grounding the scan lines via capacitors when the scan lines do not have the scan driving signals. In this way, crosstalk interference caused by energy spillover generated by neighboring data and / or scan lines can be eliminated.
Owner:LIN CHIN NAN +2

PCIE connector

The utility model relates to a PCIE (Peripheral Component Interface Express) connector, which comprises a plastic main body, terminals, a card inserting plate, a slot and a bottom, the terminal is arranged in the plastic main body, and the card inserting plate is electrically connected with the terminal; two sides of the slot are provided with placing grooves, and the placing grooves corresponding to the grounding terminals are provided with open holes. The terminal is additionally provided with a second bending part; a bulge is arranged at the bottom of the plastic main body; two sides of the terminal are provided with barb structures. The beneficial effects of the utility model are that the holes are formed in the placing grooves corresponding to the grounding terminals, so that the signal terminals and the grounding terminals are located in different electromagnetic field environments, and the crosstalk interference of the terminals is reduced; the terminal is additionally provided with the second bending part to disperse the stress of the first contact end, and the distance between the terminal and the card inserting plate is closer, so that the characteristic impedance of the connector is reduced; the barb structures are arranged on the two sides of the terminal in a staggered manner, so that the plastic main body can be prevented from warping; and the bulges at the bottom of the plastic main body are used for spacing the shoulders of the terminals, so that the short circuit phenomenon is avoided, and the performance and the service life of the connector are not influenced.
Owner:SHENZHEN GLGNET ELECTRONICS

Connector structure for improving crosstalk interference

PendingCN121748880ACoupling device detailsCrosstalk interferenceControl theory
The invention discloses a connector structure for improving crosstalk interference. The connector structure comprises a base, a first grounding connecting sheet and a second grounding connecting sheet, the base is provided with a first terminal group and a second terminal group; the first grounding connection sheet is arranged in the base and is in contact connection with a first grounding terminal arranged in the first terminal group; the second grounding connection sheet is arranged in the base and is in contact connection with a second grounding terminal arranged in the second terminal group; the interval space is arranged between the first grounding connection sheet and the second grounding connection sheet and is not conducted with each other, so that the first terminal group and the first grounding connection sheet form an independent electrical conduction loop, and the second terminal group and the second grounding connection sheet form another independent electrical conduction loop, thereby reducing the impedance path of the whole connector, and improving the reliability of the connector. When the antenna is applied to high-frequency transmission, signal attenuation is effectively reduced, and crosstalk interference is improved.
Owner:VSO ELECTRONICS

Connector with slanted grooves to parallel terminals

ActiveCN224683560UCrosstalk interferenceTrunking
The application provides a connector with inclined grooves to parallel terminals, which comprises at least one set of terminal groups and an insulating body. Each set of terminal groups contains a plurality of metal terminals, each of which is divided into a contact section, a relay section and a fixing section along a vertical axis from top to bottom and can be assembled into the insulating body. At least one sidewall of the insulating body is provided with at least one groove, and the horizontal projection area of one groove wall of the groove can correspond to the relay section of each metal terminal. The aforementioned groove wall is an inclined surface, which keeps a first included angle with the vertical axis. When each metal terminal is forced to deviate, the relay section keeps a second included angle with the vertical axis, and the second included angle is substantially the same as the first included angle, so that the relay section and the inclined surface are substantially parallel. In this way, the design of the inclined surface of the groove helps to maintain the uniform distribution of the electric field around the metal terminal, thereby effectively reducing the crosstalk interference.
Owner:AMPHENOL EAST ASIA LIMITED TAIWAN BRANCH

A method for distinguishing overlapping speech for oral examination scenarios

PendingCN122290637AData setSpoken language
This invention discloses a crosstalk discrimination method for oral examination scenarios, belonging to the field of speech intelligence technology. The method includes four steps: data preparation, feature extraction, training a discrimination model, and examination discrimination. A dataset is constructed by collecting audio from multiple examination scenarios, 80-dimensional Fbank features are extracted, and a lightweight deep learning model is used to output crosstalk confidence under mono audio conditions. Combined with threshold and multi-dimensional information for joint discrimination, accurate differentiation between target speech and crosstalk is achieved. This invention requires no additional hardware such as microphone arrays, has fewer model parameters, lower computational cost, and lower deployment cost. It can effectively suppress crosstalk interference, avoid misscoring, and significantly improve the accuracy, fairness, and robustness of oral examination scoring, making it suitable for large-scale standardized oral examination scenarios.
Owner:SUZHOU ZHIYAN INFORMATION TECH CO LTD