96 results about "Distance curve" patented technology

Determining the placement of an endotracheal tube in a patient. The invention evaluates discontinuities in the medium surrounding the endotracheal tube, such as the airway, as a function of distance past an end of the endotracheal tube. Using a loudspeaker to generate sound waves, the sound waves propagate through a coiled wavetube, a connecting adapter, and an endotracheal tube, into the area of interest. With a processing system, reflected sound waves which return from the cavity back to a microphone within the wavetube are analyzed and an area-distance curve of the area in interest is constructed.

A method, a system and a computer readable medium for dynamic mode AFM amplitude versus distance curve acquisition. In an embodiment, a constant force feedback mechanism is enabled prior to the first time an AFM probe tip contacts a sample. The feedback mechanism setpoint is iteratively reduced while at least phase and amplitude of the probe tip are recorded as a function of the relative z-height of a cantilever coupled to the probe tip. The feedback mechanism setpoint may be repeatedly swept between upper and lower bounds to average out drift between the cantilever and sample. Upon detecting a threshold, an absolute tip-to-sample distance is determined and correlated to the relative z-heights. The amplitude and phase data recorded prior to tip-sample contact is then determined as a function of absolute tip-to-sample distance.

The invention discloses a long-distance curved jacking pipe and pipe roof construction technique. The construction technique is characterized by comprising the following steps: (1) preparation, that is, the model of construction equipment is selected; (2) measuring and positioning are carried out to determine a construction position; (3) a jacking pipe platform is erected; (4) a tunnel portal is exploded, and a tunnel portal water stop device is mounted; (5) a jacking back is mounted; (6) after mounting and debugging, a pipe jacking machine enters a tunnel for jacking, and exits from the tunnel for receiving after the jacking is completed; step (6) is then repeated until a pipe roof is formed; (7) displaced grouting filling is carried out, so as to complete the pipe roof construction. The long-distance curved jacking pipe and pipe roof construction technique provided by the invention can overcome the defects of the conventional technique, and improve the pipe roof construction quality.

The invention discloses a method for regulating train speed, comprising the steps of: acquiring target distance and line data; calculating the current external resistance by using the line data; modifying a predetermined target speed distance curve according to the external resistance and the target distance to obtain the current actual train control speed; and controlling the train speed according to the actual train control speed. The embodiment of the invention also provides a corresponding device. By prestoring an ideal train control curve which only takes the brake performance of the train into account without considering the external resistance, the actual train control speed can be obtained just by modifying the current train control speed in the ideal train control curve in each train control period, thereby reducing the calculated amount, shortening the train control period and ensuring the safe operation of the train.

A method and apparatus for determining a location of a phase-to-earth fault on a three-phase electric line (30) of an electric network, comprising determining an equivalent load distance curve of the electric line (30) representing a voltage drop along the electric line scaled by an equivalent load distance of the electric line, determining a fault distance line indicating an estimate of a distance of the fault (F) from the measuring point (40) in relation to the equivalent load distance, determining a distance at which the equivalent load distance curve and the fault distance line intersect when superimposed, and selecting the determined distance as the distance between the measuring point (40) and the point of fault (F).

The invention discloses a total station prism group, a tube push bench guide system for tunnel construction and a guide method of the tube push bench guide system. The tube push bench guide system for tunnel construction comprises a laser target, a main total station prism group, a plurality of branch total station prism groups, a rear prism, a communication box and a computer. The laser target is arranged on a tube push bench in a tunnel, the main total station prism group is arranged on a mounting support in a tunnel starting well opening, the rest branch total station prism groups are arranged on tunnel segments which are arranged between the laser target and the main total station prism group and advance along with the rube push bench one by one at intervals along with the tunneling of the tube push bench. The rear prism is arranged on the wall of the tunnel starting well opening, and the main total station prism group and the branch total station prism groups are all connected with the computer. The system and the method can achieve automatic measuring of gesture of the tube push bench during long-distance curved tube pushing tunnels and guide tunneling construction of the tube push bench.

A pressure regulating valve having a compression spring fixed in a valve housing for positioning a valve plunger connected to a magnetic armature in the position above a valve seat and not electromagnetically excited, in order to create a connection between at least two pressure medium channels opening into the valve housing, and having a further compression spring disposed coaxially to the first compression spring in the valve housing, having the characteristic that the first compression spring is designed as a control spring forming a stroke and force-specific spring drive by adjusting the spring rates of both compression springs to the force/distance curve of an electromagnet by varying the current in an exciter coil, wherein the further compression spring is designed as a variably adjustable spring acting opposite to the control spring.

The invention relates to an urban main road traffic operation information processing method based on floating vehicle data. The method comprises the following steps: 1) map-matching is carried out on GPS original data transmitted by a floating vehicle, and a coordinate of a vehicle position is matched to a road network to obtain GPS operation data; and vehicle operation statuses on different road segments are displayed through combining with a map; 2), pretreatment is carried out on the GPS operation data, and the pretreatment process comprises sample screening and speed calculating; and 3), extraction of traffic operation characteristic indexes are carried out, and the average speed, the speed variance and the speed distribution are calculated; a speed-distance curve, a speed skewness coefficient, a kurtosis coefficient, a speed mileage distribution map and a speed time distribution map are output. Compared with urban main road traffic operation information processing methods in the prior art, the urban main road traffic operation information processing method based on the floating vehicle data of the invention has advantages of utilizing a taxi floating vehicle technique to analyze and process urban road traffic operation and to obtain indexes such as the road segment average speed, the speed fluctuation and the speed distribution; and the floating vehicle data of the invention has an advantage of being able to reflect a whole road segment traffic operation status, etc.

The invention provides a train track section locking time calculation method based on quasi-moving block. The method comprises the following steps of establishing a traction calculation model of a train by analyzing characteristic parameters of a quasi-moving block mode of a high-speed railway; analyzing and calculating the force applied to the train in the running process according to the traction calculation model of the train to obtain the speed-distance curve of the train in the running process: respectively establishing and solving calculation models of the train based on the track section locking time of a section and a station under the quasi-moving block mode according to the speed-distance curve of the train in the running process to obtain the track section locking time of the train based on the section and the station. The train track section locking time calculation method based on quasi-moving block can be used for drawing a train working diagram with Blocking time based on the track section locking time which is finely calculated, provides a basis for the fine use of the train receiving and dispatching routes, realizes the fine expression of the train on the occupation of the transport capacity resources, and meets the requirement of the fine management of a railway system.

The invention discloses integrated optical fiber probe type near-field optical tweezers and a method for measuring near-field optical trapping force by an AFM (Atomic Force Microscope). The AFM is used for measuring relation curves between acting forces and probe-base distances before and after light transmission, and the method is used for detecting the near field optical trapping force according to the two forces-distance curves. In a process that the AFM probe approaches and leaves a base surface to acquire the force-distance curves, by means of adding a near-field optical field outside the optical fiber probe type near-field optical tweezers, the AFM probe is exposed to the action of the optical trapping force in the process of converting an evanescent field into a homogeneous field. By the comparison of the force-distance curves before and after light transmission, the near-field optical trapping force can be calibrated for the optical fiber probe type near-field optical tweezers. According to the invention, the difficulty of a fluid mechanics detection method is overcome, and a method for measuring the optical trapping force distribution of laser near-field optical tweezers is provided.

The invention discloses a high precision leveling method and a high precision leveling device for a large optical element. The method includes: using a high-power microscope to perform continuous multiple dark field grey level image acquisition to three characteristic points at different positions on the surface of the optical element, calculating image grey level information entropy, fitting thegrey level information entropy with an axial moving distance curve of the microscope, searching for a minimal value in the curve to obtain a focusing position, and obtaining defocusing amount of eachcharacteristic point. The leveling device is in a two-plate and elastic pre-tightened design. Pitching and lateral swaying of the leveling device are adjusted through two points. By building a conversion model of the defocusing amount and adjusting amount to convert the defocusing amount of the three characteristic points into the adjusting amount of the two adjusting point, leveling operations can be performed. The problem of defocusing of the large optical element due to non-parallelism of the optical element and a focal plane of the microscope during a full-range scanning and detecting process using the microscope is solved.

The invention relates to seismic data processing technology, and provides an accurate depth domain layer speed updating method. The accurate depth domain layer speed updating method comprises the steps as follows: converting a gather data depth domain layer speed field into a root-mean square speed field so as to obtain a speed value of the position of a common depth point; calculating the offset rest speed spectra of each root-mean square speed field and common reflection point gather; carrying out energy balance processing on the offset rest speed spectra; determining the rest speed value under the maximum energy in each depth position through existing vertical rest speed spectra; updating the root-mean square speed fields by utilizing the rest speed values, thus obtaining a new root-mean square speed field, and converting the root-mean square speed field into the depth domain layer speed field in the corresponding position; and carrying out prestack depth migration processing, so as to obtain an accurate depth domain structure seism imaging result. According to the accurate depth domain layer speed updating method provided by the invention, a depth distance curve under the same phase axis is parabola heightening order correction, therefore, a rest speed spectrum with higher resolution ratio can be obtained, and reliable basis is provided for the structuring of the accurate prestack depth migration.

The invention provides an anti-falling monitoring device and an anti-falling monitoring system for an elevator as well as a monitoring method for the anti-falling monitoring system. The monitoring system comprises the elevator falling-preventing monitoring device, a data acquisition card and a computer, wherein the elevator falling-preventing monitoring device selects an incremental magnetic grid sensor; when equipment to be detected falls, a sensing band and a magnetic sensing head of the incremental magnetic grid sensor are driven to simultaneously work; the data acquisition card is used for acquiring data of the sensor in real time and transmitting the data to the computer through a shielded data cable; the computer is used for analyzing the received information and generating a speed-system distance curve which vividly reflects the operation state of a construction elevator. The monitoring system disclosed by the invention overcomes the own defects of detection equipment and test errors caused by human operation factors and has the advantages of high accuracy, wide range and distance testing range and no test limitation; the monitoring device is easy to assembly and disassembly, is also suitable for safety monitoring of equipment with similar structures, such as the elevator, and is wide in application range.

The invention discloses a force tracing method for an atomic force microscope (AFM), which relates to the technical field of micro force measurement methods and solves the problem that force signals obtained by the traditional AFM single molecule force spectrum method are easily regarded as signals generated by motions of an AFM probe but not signals generated in a dynamic process on cell surfaces. The force tracing method for the AFM comprises the following steps of: after needle feed is finished under the control of a feedback regulation system, closing the feedback regulation system, and determining a position of the AFM probe in a Z direction when the AFM probe is contacted with the surface of a tested object through an obtained force-distance curve; gradually approaching the AFM probe to the surface of the tested object, and when the AFM probe is just contacted with the surface of the tested object, closing the feedback regulation system and stopping feeding the probe to ensure that a cantilever is deflected immediately; and acquiring a relation of the deflection of the cantilever along with time by utilizing a data acquisition card. According to the force tracing method, influences of the motions in the Z direction of the AFM probe driven by a piezoelectric ceramic scanner on dynamic process researches of the surface of the tested object are avoided.

The invention provides a weighting trilateration method in a local positioning system. The weighting trilateration method comprises the following steps of: testing and fitting to obtain a distance curve corresponding to an RSSI (Received Signal Strength Indication) or LQI (Link Quality Indication) value; testing to obtain each distance average range error of the distance curve and taking the reciprocal of the percentage of the distance average range error as a weight; determining an area in which a movable node is located by utilizing three points with a strongest signal; and calculating a position of the movable node by utilizing a trilateration method, wherein the position of the movable node is obtained by a weighting method when two circles do not have a point of intersection, and theposition of the movable node is finally obtained by a manner of obtaining gravity center of the point of intersection. The weighting trilateration method in the local positioning system, disclosed bythe invention, has the advantages that defects that the traditional RSSI and LQI positioning technologies are easy to be influenced by environment inconsistency and have low precision can be overcomethrough a positioning technology.

The invention discloses a crack damage monitoring and strain field measuring method based on an FBG (Fiber Bragg Grating) sensor array spectrum. The method comprises the following steps: 1, selectinga test specimen to be measured; 2, performing structural mechanics analysis on the test specimen to be measured; 3, sticking a sensor to the test specimen; 4, performing a loading experiment on the test specimen stuck with the FBG sensor to determine an experimental system; 5, performing analysis on a series of obtained spectra to explore the corresponding relation between the characteristic parameters of the spectra and the initial positions of cracks as well as the extension conditions of the cracks; and 6, comparing the stress strain and the distance curve obtained by the FBG sensor with finite element simulation results. By virtue of the steps, crack damage monitoring and crack tip stress field measurement are realized, the corresponding relation between crack damages and spectra is achieved, and the feasibility of the method for measuring the crack tip strain field can be verified through experiments.

The invention relates to a target distribution law-based abnormal human behavior detection method. A pre-trained depth learning network is used, according to deployment scene target learning trainingfine adjustment parameters, target detection is carried out, and the states of a person and an object in the scene are detected; according to a set state abnormal alarming point, abnormal alarming istriggered and carried out; the real-time positions of the person and the object in an area are acquired at the same time; the position information is returned; an area target point is set, the distance between the person position and the target point is calculated, the distance between the object position and the target point is calculated, the distances between the person and various objects arecalculated, the calculation results form curves, an object distribution activity curve, a person state activity curve and a curve of the distance between the person and a preset marking item are formed respectively, and a long-term iteration regression curve is acquired; and when the curve fluctuation exceeds a preset deviation range and does not satisfy long-term law and special date law curves,an abnormity is triggered for alarming and reminding.

The invention discloses a crossed crossover track distance measuring method and device based on a multi-rotor unmanned aerial vehicle. During the measurement process, a multi-rotor unmanned aerial vehicle flies at a fixed distance along two crossed crossover tracks successively; with a UAV spatial positioning technology and an IMU angle detection technology, three-dimensional spatial point cloud data of detection region space are obtained by combining distance data scanned by a two-dimensional laser radar and then a crossed crossover clearance distance curve model of an overhead transmission line is established, thereby realizing accurate measurement of the crossed crossover clearance distance of the overhead transmission line. Therefore, problems of low efficiency and precision, poor environmental adaptability and poor good real-time performance of the existing crossed crossover track inspection method can be solved. The crossed crossover track distance measuring method and device have advantages of convenient and safe operation, high measurement precision, and high efficiency.

The invention relates to a method and device for calculating car distance and collision time with functions of improving car distance calculation accuracy and performing accurate real-time early warning. The method comprises the steps of image acquisition, wherein a vehicle-mounted camera of the own vehicle acquires an image of a front car; front car detection and tracking, wherein the image is processed, and position information of feature points of the front car is detected; front car distance calculation, wherein the position information of the feature points of the front car in a predetermined group is taken, the width of the front car and the car distance are calculated to obtain an average width value of the front car, and the car distance between the own car and the front car is corrected according to the average width value of the front car; front car collision early warning, wherein a relative car distance curve is acquired, real-time relative speed is obtained according to the car distance curve, collision time is calculated, the collision time is compared with an early warning threshold, and it is judged whether or not early warning is triggered; the relative car distance curve is obtained by fitting a Bezier spline, and the corrected car distance is taken as an input value of the Bezier spline.

The invention discloses a guidance law analysis method with attack time and seeker view field constraint. The method comprises the following steps: establishing a guidance equation of intercepting a static target in a two-dimensional horizontal plane by a missile; designing an intermediate variable related to the missile preposition angle, and converting the guidance equation into a differential equation based on the intermediate variable to obtain a guidance law expression; designing a quadratic function based on the intermediate variable as an expected relative distance curve; realizing theview field angle constraint of the seeker through the condition that the first derivative of the expected curve is greater than zero; and based on boundary conditions and attack time constraints, unknown parameters of the expected curve are solved, and a guidance law and an attack time reachable domain in an analysis form are obtained. The method adopts an analysis method based on relative distance remodeling, does not need to linearize the model, does not depend on estimation of remaining time, is suitable for guidance tasks with attack time constraint and limited strapdown seeker field of view, and has the characteristics of simple design, high reliability, strong applicability and the like.

The invention discloses a totally-smooth screw rotor, and belongs to the technical field of dry type double-screw vacuum pumps. The molded lines of the end face of the screw rotor are composed of seven sections of curves, the adjacent curves are totally in smooth connection, and sharp points do not exist. A tooth crest arc CD and a tooth root arc FG are in smooth connection through a section of arc DE and a section of cycloid equal-distance curve EF which are engaged in a conjugate manner, the tooth root arc FG and a circle involute AB are in smooth connection through a cycloid equal-distance curve GA, and the circle involute AB and the tooth crest arc CD are in smooth connection through an arc BC. During work, the molded lines of the end faces of two screw rotors are the same and can be in accurate engagement. The screw rotor spirally unfolded in the axial direction from the molded lines of the end face of the screw rotor is composed of seven tooth faces, all tooth faces of the screw rotor are in smooth transition, and the area where stress concentration is likely to happen is eliminated. The screw rotor has the beneficial effects of being high in strength, good in sealing performance, small in abrasion and long in service life.

The invention provides an echo view registration method for a sub-aperture altimeter, which comprises the following steps of: multiplying a signal by a frequency scaling function to remove distance curved spatial variability; performing inverse fourier transform in a distance direction, multiplying by a conjugation of the inverse fourier transform of a certain function, namely a residual video phase correction function, and finishing residual video phase correction, namely 'deskew' processing; multiplying by an inverse frequency scaling function, namely eliminating a secondary phase error introduced by the frequency scaling function to finish scaling processing; multiplying the scaled signal by a linear phase function to perform distance migration correction so as to finish registration in a view distance direction; performing azimuth compression on an obtained sub-view of the view distance registration to obtain a compression sub-view corresponding to an aperture; and performing registration in an azimuth direction on all the obtained compression sub-views, and extracting each azimuth-registered equivalent sub-view unit for subsequent tracking estimation or imaging processing.

The present invention relates to a method for active classification and positioning of underwater targets based on a reliable sound path. The method comprises the steps of: employing an active detection method to obtain a pitch angle-distance two-dimensional diagram in a target scene, drawing a pitch angle-distance curve according to a reliable sound path, employing the curve to perform target classification to extract pitch angles and distances of underwater targets, and combining sound field information to convert the pitch angles and the distances of the underwater targets to horizontal distances and depths to obtain location results. The method for active classification and positioning of the underwater targets based on the reliable sound path can perform effective positioning of the targets in a deep sea environment.

The invention relates to an automatic positioning method and a device for tips of different micro pipettes in an automatic microinjection system, belonging to the field of automatic microinjection system. The present invention provides an automatic positioning method for different micro pipette tips in an automatic microinjection system in order to solve the problem that the existing needle tip positioning method is difficult to separate the injection needle from the background, so that the needle tip position of the suction needle cannot be accurately positioned. The automatic positioning method comprises the following steps: pre-processing the acquired original image; the pixel value difference being made between the filtered image and the denoised image; determining a maximum connectingarea of a predetermined number; making the circumscribed rectangle of the connected region, and determining the average position of the intersection point of the circumscribed rectangle and the imageboundary as the root position of the needle tip; calculating the distance between all points in the outer contour and the root position, and the included angle between the line segment connected withthe root position and the horizontal axis of the image; making a distance curve to determine the position of the tip of the needle. The invention is suitable for automatic microinjection of organisms.

The invention provides a plane sight distance analysis method based on AutoCAD. The method comprises the steps that the drawing environment of CAD software is initialized; a viewpoint trajectory curve is generated, wherein the linetype entity of the curve is a polyline; the starting point and the end point of the viewpoint trajectory curve and the total length parameter of the viewpoint trajectory curve are acquired; parameters which comprise the sight distance envelope line fitting accuracy, the driving sight distance and the sight line generation spacing are input into an interactive interface; the starting point and the end point of the first set of straight lines are acquired; the number of cycles is set and T corresponding cycles are carried out to successively acquire all driving sight line intersections, and the driving sight line intersections are successively stored into a list; a drawing layer in CAD software is set as a sight distance curve; and a Pline command in CAD software is used to restore all intersections in the list to acquire a sight distance envelope line. According to the invention, the method makes full use of the computing ability and the drawing function of a computer; the design quality is improved; the safety of road operation is ensured; and the method is easy to learn and use, has the advantages of fast execution speed and the high flexibility, and is suitable for the engineering design.