78 results about "Surface flatness" patented technology

This utility model discloses a mold inspection platform, including a base plate. A base frame is fixedly connected to the upper surface of the base plate. A worktable that moves vertically is arranged above the base frame via a driving mechanism. A fixed clamping plate is fixedly connected to one end of the upper surface of the worktable, and a movable clamping plate that moves horizontally is arranged at the other end of the upper surface of the worktable. A first receiving box is fixedly connected to the top of the fixed clamping plate. This invention relates to the field of mold inspection technology. This mold inspection platform can clamp and fix the mold by moving the movable clamping plate in conjunction with the fixed clamping plate. After the mold is fixed, the first transmission mechanism drives the movable box to descend. After the inspection head assembly contacts the top of the mold, the surface flatness of the mold can be inspected. Then, the second transmission mechanism drives the inspection head assembly to move, allowing inspection of different positions of the mold, thus improving the efficiency and quality of mold inspection.

The utility model relates to a kind of vibration auxiliary devices for concrete pouring, it includes frame body, forming mould on frame body and vibration pump, frame body four corners are separately provided with up-down telescopic support, support is adjusted height by screw rod or hydraulic mechanism to accurately control the horizontal state of frame body and mould;Vibration pump is fixed to frame body bottom and is contacted with mould, and short frequency vibration is promoted to make concrete mortar uniform flow and discharge bubble.The device is applicable to prefabricated concrete component, kerbstone and other standardized production scene, and the internal compactness and surface flatness of concrete product can be effectively improved.The utility model can respectively fine tune each fulcrum height by the independent adjustable support of frame body four corners, realize millimeter level horizontal calibration of mould, avoid uneven distribution of concrete slurry due to inclination, significantly reduce honeycomb, pockmark and other defects, and improve product compactness and surface quality.

The application provides a door body assembly and a cooking equipment, relates to the technical field of kitchen appliances, and aims to solve the technical problem of air leakage caused by poor flatness of an inner glass after assembly. The door body assembly is provided with at least two first supporting members and two second supporting members. The two first supporting members are arranged on the stepped surfaces of two first supports respectively, and the two second supporting members are arranged at the ends of the two first supports respectively. The first supporting members are provided with first supporting surfaces, the second supporting members are provided with second supporting surfaces, the areas of the first supporting surfaces and the second supporting surfaces are smaller than the area of the stepped surfaces, the second door body is arranged on the first supporting surfaces and the second supporting surfaces and is attached to the first supporting surfaces and the second supporting surfaces respectively. In this way, the supporting area for supporting the second door body is reduced, the influence of the flatness of the supporting surfaces on the second door body is reduced, the surface flatness of the second door body is ensured, and the problem of air leakage caused by poor surface flatness of the second door body is avoided.

The application provides a kind of tinned plate detection device, belongs to plate detection technical field, including detection frame and plate feeding and spreading component, the plate feeding and spreading component is two groups, symmetrically installed in the middle of the inner side wall of detection frame, the top of the inner side wall of the discharge end of detection frame is installed with a detection mechanism.The application is raised by roller pressing mechanism and primary detection mechanism, then the plate is worn between two plate feeding and spreading components, so as to clamp and transport the side edge of plate by plate feeding and spreading component, so that it can automatically cross detection device to complete feeding, reduce the dependence on manual, simplify the operation mode, improve the detection efficiency, and when plate feeding and spreading component is separated from plate at the end of conveying, transverse tension can be applied to both sides of plate by plate feeding and spreading component, to offset the edge wave, middle wave and buckling of plate caused by stress, to ensure the accuracy of surface flatness and thickness data collection.

Conventional substrate manufacturing processes face several challenges, including technical bottlenecks in areas such as cost reduction, the production of large substrates, and especially ensuring surface flatness. [Solution] The present invention provides a laminated substrate structure comprising a first bonding layer, a second bonding layer, and an adhesive layer. The first bonding layer comprises a plurality of adjacent first bonding substrates and a plurality of first bonding gaps located between the first bonding substrates; the second bonding layer comprises a plurality of adjacent second bonding substrates and a plurality of second bonding gaps located between the second bonding substrates. The adhesive layer is positioned between the first bonding layer and the second bonding layer and defines a first adhesive surface and a second adhesive surface, connecting the first bonding layer and the second bonding layer. At least some of the first bonding gaps and second bonding gaps do not overlap along the first adhesive surface, the second adhesive surface, or the projection direction of both perpendicular to the adhesive layer.

The application belongs to the technical field of PCB plating, and relates to a high-precision LED PCB and a preparation method thereof, which comprises the following steps: pretreating a PCB substrate, wherein the PCB substrate has a through hole; depositing a first conductive layer on the hole wall of the PCB substrate; depositing a first metal layer on the surface and the hole wall of the PCB substrate; using a developing exposure process to make a resist film cover part of the surface of the circuit board and expose the through hole area of the surface of the circuit board, so as to form a plating pattern; depositing a second metal layer on the hole wall of the preset through hole area of the PCB substrate to obtain a preliminary product; and post-treating the preliminary product, wherein the post-treatment comprises resin hole plugging, film stripping and grinding to obtain the LED PCB. The application realizes a breakthrough in precision and reliability, greatly improves the product quality consistency, obtains a very high surface flatness of the copper surface, significantly optimizes the production efficiency and cost benefit, and provides a replicable paradigm for industry upgrading.

The present application relates to a kind of methods for preparing thick electrode based on dry film preparation process, comprising the following steps: (1) according to certain proportion, active material, forming auxiliary agent, non-fibrous and fibrous binder, pore-forming agent, leveling agent are weighed;(2) active material and non-fibrous binder, active material and forming auxiliary agent, pore-forming agent, fibrous binder are respectively mixed to carry out high-speed stirring shear;(3) adjusting roller press, the mixed powder is rolled, and electrode film is obtained;(4) electrode film is placed into moulding press and heated and pressed, to remove pore-forming agent;(5) with spatula, even coating is applied on the surface of electrode, and again moulding is pressed, to improve the flatness of electrode film, and improve the bonding force of electrode film and current collector;(6) adjusting the temperature of roller press, axle distance, and electrode film is laminated and rolled with current collector, and thick electrode is obtained.Compared with prior art, the present application can prepare homogeneous thick electrode without crack, and improve area load capacity.

This application discloses a thin film and its preparation method, an optoelectronic device and its preparation method, and a display device. The material of the thin film includes inorganic particles. The thin film described in this application has low roughness and good surface smoothness.

The utility model provides a kind of to cut glue port device, mould and punch cutting mechanism, the mould is equipped with injection cavity, and pouring piece and product are formed by injection in injection cavity, the pouring piece includes connecting portion, and the connecting portion is connected with product;The punch cutting mechanism extends to the mould inside and cuts, the punch cutting mechanism includes upper and lower symmetrical cutter one and cutter two, the blade of cutter one and cutter two is aligned with the connecting portion of product and pouring piece and is cut, and smooth cutting surface is formed, after the product after cutting is taken out, the pouring piece continues to be placed in the injection cavity and carries out next injection, saves injection material, using upper and lower symmetrical cutter one and cutter two synchronous punch design, significantly improve cutting surface flatness and product yield rate, simultaneously, after the product after cutting is taken out, pouring piece is located in injection cavity so that pouring piece can be recycled and utilized, reduce production cost.

This invention provides a polypropylene film surface flatness testing device, belonging to the field of film production technology. Addressing the problem that films are soft materials and their edges are prone to folding during testing, existing testing devices are inconvenient for flattening the folded areas of the film, easily misidentifying folded areas as unevenness and affecting testing accuracy. This invention solves the problem of existing testing devices being unable to flatten the folded areas of the film, as the film's edges are easily folded during testing due to its softness. The device includes a base plate, with a first support fixedly connected to the top of the base plate, and a second support fixedly connected to the top of the first support. Both the first and second supports are equipped with flattening components, each including a control mechanism and two sets of connecting mechanisms. A first roller group is located on the left side of the first support and the right side of the second support, and a second roller group is located on the top right side of the first support and the top left side of the base plate.

An ultra-thin aluminum composite television back panel comprises an aluminum composite matrix consisting of a surface aluminum plate, a corrugated aluminum alloy core layer, and a bottom aluminum plate. The surface and bottom aluminum plates are made of high-purity aluminum alloy with a thickness of 0.2-0.5 mm, accounting for 40-60% of the weight; the core layer has a corrugation height of 0.5-1.0 mm and accounts for 30-50% of the weight. Nanoscale carbon fibers with a mass fraction of 5-10% and an aspect ratio of 20-60 are distributed within the matrix as a reinforcing phase. The back panel exhibits a gradient thickness structure, thicker at the edges and thinner at the center, with an edge thickness of 1.2-1.5 mm and a center thickness of 0.8-1.2 mm. Due to its unique composite structure and reinforcing phase distribution, the back panel exhibits excellent comprehensive performance, with a flexural strength greater than 200 MPa, a thermal conductivity greater than 150 W / m·K, and a surface flatness of less than 0.1 mm / m, achieving ultra-thinness while simultaneously meeting the requirements for high-strength support and efficient heat dissipation.

The present invention provides a film used as a support in the process of manufacturing resin films by the solution casting method, which exhibits excellent surface flatness, solvent resistance, and dimensional stability. The support film of the present invention has a structure in which a resin layer is provided on at least one surface of a polyester film. The resin layer contains an acid-modified polyolefin resin, a crosslinking agent, and polyvinyl alcohol with a saponification degree of 99.0% or less and an average degree of polymerization of 1000 or more. The polyvinyl alcohol content is 5 to 500 parts by mass per 100 parts by mass of the acid-modified polyolefin resin. The dimensional change rate in the TD direction is 2.0% or less after heat treatment at 160°C for 15 minutes, and the ratio of the dimensional change rate in the MD direction to the dimensional change rate in the TD direction is 0.5 to 1.5.

This invention relates to the field of electronic packaging substrates, and particularly to an alumina ceramic substrate material, its preparation method, and its application. The alumina ceramic substrate comprises 90-99 wt% alumina and 1-10 wt% sintering aids. The sintering aids have the following composition: xB₂O₃·zSiO₂·yBi₂O₃, where 15≦x≦25, 50≦y≦70, 15≦z≦25, and x+y+z=100, where x:y:z is the mass ratio. The density of the alumina ceramic substrate is ≥3.8 g / cm³. 3 The alumina ceramic substrate of this invention has the following characteristics: surface roughness ≤ 0.35 μm, breakdown strength ≥ 35 kV / mm, bending angle ≥ 350 MPa, and thermal conductivity ≥ 25 W / m·K. It also features high density, uniform microstructure, good surface flatness, high mechanical strength, high breakdown strength, low dielectric loss, and high thermal conductivity.

An object holder configured to support an object is provided. The object holder has a support surface having multiple support elements comprising a metal-Si multilayer film, a metal-Ge multilayer film, and / or a chromium nitride layer, and the individual heights of the support elements can be selectively changed by heat treatment of the metal-Si multilayer film, the metal-Ge multilayer film, and / or the chromium nitride layer. Also provided are an object table comprising such an object holder, an apparatus for controlling the flatness of a surface comprising such an object holder, an optical element for a lithography apparatus, an apparatus for controlling the flatness of a surface, a lithography apparatus or tool comprising such an object holder, a method for controlling the shape of a surface, a method for manufacturing an object holder, a method for correcting the flatness of an object holder or optical element, and the use of such an apparatus or method in a lithography apparatus or process.

A self-supporting box formwork system for large-span hollow floor construction, comprising: a plurality of columns, the top of the column being fixedly provided with a support frame; a plurality of spliced bottom forms, the spliced bottom forms being laid and installed on the support frame, the plurality of spliced bottom forms being mutually spliced through a clamping structure and forming a continuous pouring bottom surface; and a plurality of self-supporting box forms, the self-supporting box forms being detachably installed on the spliced bottom forms, and the adjacent self-supporting box forms being reserved with intervals and forming rib beam channels. The support frame is used to replace the traditional full-dense support, the number of vertical rods and connecting pieces is greatly reduced, the lower operation space is released, the passing, transportation and multi-work cross construction are facilitated, and the construction organization is more efficient. The continuous support, higher stiffness and more accurate forming are realized: the support frame cooperates with the cross beam to uniformly support the spliced bottom form, the overall stiffness is significantly improved, the settlement, sagging and joint misalignment are effectively reduced, the bottom surface flatness and elevation control are more stable, and the floor forming quality is higher.

This invention relates to an ultra-flat nickel (100) single-crystal thin film and its preparation method. The method involves depositing a nickel thin film on the surface of an A-plane single-crystal sapphire substrate using physical vapor deposition. The nickel thin film is then subjected to high-temperature annealing in a reducing protective atmosphere to obtain a single-crystal nickel thin film with a (100) orientation. By selecting an A-plane single-crystal sapphire with a (11-20) crystal orientation as the epitaxial substrate, it exhibits excellent lattice matching with the Ni (100) plane (mismatch <5%), effectively inducing the epitaxial growth of the nickel thin film along the [100] direction and suppressing the nucleation and growth of grains with other orientations. Furthermore, the prepared nickel (100) single-crystal thin film possesses advantages such as atomic-level surface flatness (Ra < 1 nm), absence of twin defects, and high crystal orientation consistency, meeting the stringent material quality requirements of high-end devices.

This invention belongs to the field of building technology, and particularly relates to a wind tunnel construction method and structure combining cast-in-place and prefabricated construction. It includes the concrete pouring of the wind tunnel structure's top slab, bottom slab, and cast-in-place sidewalls, as well as the connection of the prefabricated curved section components at the bottom and top of the wind tunnel structure, and the prefabricated sidewalls to the aforementioned concrete structures via tenons and mortises to form tongue-and-groove joints. This invention uses a prefabricated construction method to create the curved sections on the wind tunnel cross-section, avoiding the difficulties of vibration during cast-in-place construction of curved sections, reducing the probability of construction quality problems, and achieving high-quality completion of the wind tunnel's concrete structure. The curved sections are prefabricated in a factory, ensuring a high quality assurance rate for the prefabricated components and enabling precise control of surface flatness. This is of great significance for ensuring the quality of the wind tunnel flow field and improving the quality and accuracy of wind tunnel laboratory tests.

This invention provides a standard silicon wafer for calibrating surface flatness measurement equipment. The standard silicon wafer includes a silicon substrate layer and a roughening layer formed on its surface. The surface roughness of the roughening layer can be precisely controlled within the range of 0.1 nm to 2 nm, and its roughness uniformity is no greater than 35%. This invention, by directly forming the roughening layer on the substrate, fundamentally solves the problems of easy particle detachment, poor stability, and difficulty in controlling uniformity inherent in traditional particle-coated standard wafers. This standard silicon wafer features structural stability, controllable parameters, and high uniformity, providing a reliable and traceable calibration benchmark for surface flatness measurement equipment such as atomic force microscopes and scanning electron microscopes, significantly improving the accuracy and consistency of surface morphology measurements in semiconductor manufacturing processes.

The application relates to the technical field of ceramics, and discloses a skin glaze, dark skin glaze ceramic tiles and a preparation method thereof. The skin glaze can effectively expand the glaze melting temperature range, stabilize high-temperature viscosity, inhibit excessive glaze layer flow during the firing stage, avoid physical disturbance to the ink form, and significantly improve the problems of pattern edge blur, ink scattering, color phase unevenness and the like through the synergistic effect of SrO and ZnO; meanwhile, the SrO and ZnO synergistically control the glaze melt crystal precipitation behavior, optimize the microcrystal distribution and surface flatness, thereby improving the smooth and delicate touch of the glaze surface, eliminating defects such as bright spots, dull spots, roughness and dryness, and guaranteeing the appearance and texture stability of the skin glaze. In addition, the skin glaze further introduces B2O3, which can be used as a low-temperature fluxing agent to reduce the glaze melt viscosity, improve the leveling property, reduce defects such as pinholes, glaze shrinkage and corrugation, and improve the glaze layer density, and B2O3 can also synergistically stabilize the high-temperature viscosity with ZnO and SrO, optimize the ink color development environment, and improve the satin gloss feeling and gloss stability of the glaze surface.

This utility model relates to the field of automotive bracket technology, and more particularly to a surface flatness control device for the demolding process of an automotive bracket mold. It includes: a worktable, a support frame on the worktable, a switching component on the top of the support frame, a mold component on one side of the bottom of the switching component, and a flattening demolding component on the side of the bottom of the switching component away from the mold component. By setting up the switching component, a motor drives a lead screw to rotate, enabling rapid switching between the upper mold and the mounting plate, thus improving the automation and operational efficiency of the demolding process. Furthermore, by setting up the flattening demolding component, the position of the brush can be adjusted by extending and retracting the telescopic rod of the telescopic cylinder five according to the size and specifications of the material. The brush can remove burrs and minor imperfections from the surface of the material during its ascent, improving the surface flatness of the material.

The utility model relates to packing film processing technical field discloses a kind of smoothing mechanism for nano silver copper packing film processing, including processing table;Motor one, the motor one is installed in the inside of the processing table;Intermeshing gear and rack plate, the gear is fixedly connected in the output end of the motor one;Connecting plate and mounting block, the connecting plate is fixedly connected in the outside of the rack plate, the mounting block is fixedly connected in the bottom of the connecting plate;Smoothing scraper, the smoothing scraper is installed in the inside of the mounting block, smoothing scraper outside is provided with smooth coating;And dismounting component. In the utility model, it is realized by the traditional smoothing mechanism to change packing film constantly from the lower part of smoothing scraper by the roller rolling pressure of multiple adoption, it is convenient to remove bubble and wrinkle on packing film, ensure the surface flatness of packing film, to improve the conductivity and sealing property of product.

The utility model discloses a kind of devices for measuring flatness, magnetic force disc is detachably installed on the movable part on tilting table, multiple positioning strip magnetism is absorbed on magnetic force disc, column is installed on the fixed part on tilting table, one end of cantilever is rotatably installed on column and is locked by bolt, height gauge is slidably installed on the other end of cantilever and is locked by bolt, the detection end of height gauge is towards workpiece between positioning strip. When using the device to measure the surface flatness of workpiece, multiple positioning strips can be used to form a limiting space around the workpiece first, then the workpiece is placed in the limiting space, which is convenient to operate and can adapt to workpieces of various sizes. Moreover, the angle of the tilting table can be adjusted according to the inclination angle of the surface to be measured of the workpiece to compensate for the inclination angle of the surface to be measured of the workpiece to make it level, facilitating the measurement of the height gauge. The device is simple and convenient to operate, greatly shortens the time in the placement and position adjustment of the workpiece, and improves the efficiency.

This invention relates to the field of welding technology and provides a welding device and its working method for component connections. The device includes a worktable, a welding robot mounted on the top of the worktable for welding components, and a positioning component mounted on the top of the worktable. The positioning component includes a limiting mechanism that slides on the top of the worktable. This device solves the problem of welding defects caused by surface flatness defects and dimensional tolerance fluctuations in the components to be welded, resulting in poor contact of the docking reference surface, uneven gaps, and misalignment of the assembly reference. The device reduces sliding resistance by setting up a retaining tube mechanism around the four corners of the inner wall of the frame, using a wheel with a tapered section to roll and contact with the edge of the second component. Real-time data acquisition via a micro-motion sensor and closed-loop linkage of a bidirectional cylinder with the control system compensates for wheel wear, corrects the component sliding posture, ensures the verticality of the second component's vertical sliding, avoids docking deviations, and improves the docking accuracy and welding consistency of the components.

This invention relates to the field of optical inspection technology for sheet metal surfaces, specifically to an optical-based method and system for detecting the flatness of sheet metal surfaces. The method includes: projecting an optical pattern with a specific spatial coding structure onto the surface of the sheet metal to be tested, and acquiring the original deformed image by obtaining a surface-modulated deformed pattern. The image is preprocessed to eliminate environmental interference and extract the effective area. Based on the spatial coding structure, the effective area image is decoded to reconstruct a two-dimensional height displacement field of the sheet metal surface relative to a reference plane. Based on this height displacement field, the local curvature distribution of the surface at multiple scales is calculated and the global undulation trend is analyzed. By comparing with a preset flatness threshold, various defect areas are accurately identified. The defect areas are classified and parameterized to generate a detailed inspection report containing information on defect type, location, size, and depth. This invention improves the accuracy, anti-interference capability, and interpretability of defect analysis in flatness detection.

This invention discloses a fixed-length cutting device and method for eaves panels, relating to the field of building material processing technology. The invention includes a feeding frame with limiting components on both sides of its upper part. Each limiting component includes two mounting frames fixedly connected to the front and rear ends of the top of the feeding frame, with a common baffle movably connected to each frame. A cutting component is positioned above the feeding frame, and a detection component is located on one side of the feeding frame. This invention uses a baffle, a first pressure plate, and a second pressure plate to fix the specified length of the panel on the feeding frame for cutting, solving the problem of inconvenience in fixed-length cutting of panels. It also uses a blower housing and blower pipe to clean the area to be cut, solving the problem of inconvenience in cleaning the cutting area. Finally, it uses a measuring rod and measuring wheel to detect the surface flatness of the panel, solving the problem of inconvenience in detecting the flatness of the panel before cutting.

This invention provides a titanium powder roll forming device, comprising a parallel gantry frame, a worm gear passing through the gantry frame, and an adjusting motor. The lower part of the worm gear is rotatably connected to a convex upper roll via a connecting block, and a concave lower roll forms a forming channel. Both the upper and lower rolls are independently connected to a geared motor for bidirectional drive, and work with a screw feeder and an inclined discharge plate to achieve efficient material transfer. By adjusting the gap between the upper and lower rolls and the guide structure of the worm gear, precise adjustment of the titanium powder billet thickness and stability of the rolling process can be achieved. The adaptive design of the convex roll slope angle and the concave roll groove, combined with the high-pressure rolling process, significantly improves the density and surface flatness of the titanium sheet. This device solves the problems of large thickness deviation and insufficient density in traditional rolling technology.

The present application relates to the technical field of steel member, and particularly relates to a manufacturing method of steel cross beam, which comprises the following steps: segmenting design drawings of the steel cross beam according to the design length; further segmenting the beam segment at the end to form a first end segment and a second end segment with an end sealing plate, and the length of the first end segment is less than that of the second end segment; providing a jig frame, and assembling the first end segment on the jig frame; after the assembly of the first end segment is completed, machining the end sealing plate on the first end segment to make the surface flatness of the end sealing plate meet the design requirements; providing a general assembly jig frame, and continuously assembling the second end segment and the remaining beam segments on the general assembly jig frame and completing the butt joint; transporting the machined first end segment to the general assembly jig frame, and butt joint connecting the first end segment and the corresponding second end segment, so that the manufacturing of the steel cross beam is completed. The present application can ensure that the flatness of the end sealing plate meets the accuracy requirements.

The utility model relates to a film pasting equipment technical field, concretely relates to an intelligent film pasting machine, including the board input device, detection device, film pasting device and board output device that set up in order from front to back, the board input device is used to stack the board one by one to the rear delivery, the detection device includes surface detection mechanism and thickness detection mechanism, the surface detection mechanism is used to detect the board surface flatness of board input device delivery, the thickness detection mechanism is used to detect the board thickness of board input device delivery, the film pasting device is used to carry out film pasting to the board that has passed surface detection mechanism detection, and the film pasting device can realize adaptive film pasting according to the detection information of thickness detection mechanism, the board output device is used to receive the board that is outputted by film pasting device, and carries out the classified stacking of board, the utility model solves the problem that the film pasting quality of existing film coating device is poor, and the problem of low yield.

The application discloses a preparation method of a vacuum chuck with high surface flatness for wafer processing. The method uses chloride ion-free hydratable magnesium oxide and tea polyphenol as raw materials, and prepares a porous ceramic sheet with high surface flatness through pressure filtration forming and high-temperature sintering. The porous ceramic sheet prepared has a pore diameter of 80-300 nm, a porosity of 42%-67%, and a flatness of less than 20 nm on the surface without polishing. The porous ceramic sheet can be loaded into a metal holder to form the vacuum chuck with high surface flatness.

This utility model relates to the field of flatness testing technology, and more particularly to a device for testing the surface flatness of precast concrete components. It includes a mounting frame, a laser level, connection ports, a lens, and a lifting mechanism. The laser level is mounted on the mounting frame and has two connection ports. A lens is mounted on the laser level. The lifting mechanism is also mounted on the mounting frame. The device further includes a first anti-vibration pad, elastic elements, a second anti-vibration pad, and a base shell. The second anti-vibration pad is mounted on the base shell, and the first anti-vibration pad is mounted on the lifting mechanism. Two elastic elements connect the first and second anti-vibration pads. The second anti-vibration pad absorbs low-frequency, large-amplitude vibrations transmitted from the ground. Mechanical vibrations generated during device operation are absorbed and buffered by the first anti-vibration pad and the elastic elements, keeping the laser level stable and ensuring that the laser emitter does not deviate due to minor vibrations, thus guaranteeing the accuracy of the measurement data.