446results about How to "Strong stability" patented technology

The invention relates to a method for detecting a multi-lane line on basis of a random sample consensus (RANSAC) algorithm, which comprises the following steps: step 1, the initial image of the road condition in front of a car is acquired, i.e. during the travelling process of the smart car, acquiring the initial image of the road condition in front of the car is acquired through a camera which is installed on the car; step 2, the initial image which is obtained in the step 1 is subjected to inverse perspective mapping for obtaining an inverse perspective drawing; step 3, a two-dimensional Gaussian core is utilized to carry out image preprocessing on the inverse perspective drawing in the step 2; step 4, Hough transformation is carried out on the preprocessed image, so a lane candidate line is obtained, the quick RANSAC verification is carried out on the lane candidate line through utilizing the Hough transformation, and the revised lane candidate line is obtained; and step 5, the revised lane candidate line which is obtained in the step 4 is post-processed. Consequently, the method has the following advantages that the method has strong stability, identifies the multi-lane line and can better solve the problem of the crooked lane.

The invention provides a working area ranking method and ranking system for a robot. The method includes the steps of S10 dividing the working area into a plurality of working sub-areas according to a working area map of the robot, S20 calculating distances between adjacent working areas according to the adjacent relationship among the working sub-areas, and S30 ranking the working sub-areas according to the current working sub-area of the robot, the adjacent relationship among the working sub-areas and the distance between the adjacent working areas. The working area is segmented before cleaning to obtain a plurality of working sub-areas, each of which is regularly shaped. Ranking of the working sub-areas is facilitated, and planning a cleaning path for each working sub-area is more convenient, so that total path of the robot travels in the working sub-areas is the shortest. The cleaning efficiency of a sweep robot is improved.

The invention relates to the field of unmanned aerial vehicle (UAV) and ground robot coordinated formation, and provides a system which has good scalability and strong stability and can support UAV and ground robot platform coordinated formation so researchers can conduct physical simulation and experimental verification on an air-ground coordinated formation algorithm through the system. The technical scheme is as follows: a UAV and ground robot coordinated formation system is composed of a UAV formation, an indoor positioning system, ground mobile robots, and a ground work station; the UAV formation includes multiple four-rotor UAVs of different models, and each UAV is equipped with an airborne controller, a sensor device and a Wi-Fi module; and the airborne controllers run a flight control algorithm in real time and are responsible for coordinating and commanding all behaviors of the UAVs, and the attitude information of the UAVs is acquired by the sensor devices. The system is mainly applied to the occasion of UAV and ground robot coordinated formation.

The invention discloses a method for preparing high-concentration nano silver monomer dispersion liquid. A nano silver stabilizer, a silver source and a silver ion complexing agent are dissolved in water in sequence, and a reducing agent is added after stirring is carried out for a certain period of time; and stirring continues, the mixture stands and ages, and the target high-concentration nano silver monomer dispersion liquid is obtained. According to the method, the high-concentration nano silver monomer dispersion liquid is obtained at low temperature through the very moderate polyol weak reducing agent rather than a strong reduction reaction. The size of nano silver particles prepared through the scheme ranges from 5 nanometers to 10 nanometers, the nano silver particles have monodispersity, and the agglomeration phenomenon is avoided. The antibacterial liquid has the characteristics of being high in stability, high in antibacterial rate, wide in antibacterial range and the like. The preparation method is easy and convenient to operate, the parameter adjustment range is wide, energy consumption is low, the period is short and the method is suitable for scale-up and industrial big production.

The invention provides a hybrid type tilting rotor-wing unmanned aerial vehicle. The hybrid type tilting rotor-wing unmanned aerial vehicle comprises a vehicle body, a power system, a control system and a tilting mechanism. The vehicle body comprises a fuselage, wings and an empennage; the power system is composed of screw propeller power cabins which are located at two ends of the wings and a tail duct power cabin; each power cabin can be tilted for a large angle; the control system can be used for carrying out stabilization and posture control on parallel flight and vertical flight states of the unmanned aerial vehicle; the tilting mechanism is responsible for changing tilting angles of the three power cabins. When the unmanned aerial vehicle is at a multi-rotor-wing mode, the unmanned aerial vehicle can vertically ascend and descend and suspend in the air; when the unmanned aerial vehicle is at a fixed-wing mode, the flight speed is relatively rapid and the efficiency is relatively high. The hybrid type tilting rotor-wing unmanned aerial vehicle fuses advantages of multi-rotor wings and a fixed wing, and has wide application prospect.

The embodiment of the invention discloses a resource load balancing control method and a cluster scheduler. The method includes the steps of predicting performance data of applications deployed on each cluster node within a preset time period; calculating a first standard deviation of a cluster system according to the predicted performance data of each cluster node; under the condition that the first standard deviation of the cluster system is greater than a preset threshold value, an application migration scheme is determined according to a resource load balancing rule; sending the application migration scheme to a cluster application manager to trigger the cluster application manager to conduct balancing control over resource loads of the cluster system according to the application migration scheme. By means of the embodiment, the migration effectiveness can be improved, and meanwhile the balancing control over the resource loads of the cluster system is more accurately conducted.

The invention provides a corridor vanishing point rapid detection algorithm based on a K-means method. The method is characterized by carrying out earlier stage processing comprising down-sampling, gray processing, histogram equalization and Canny edge detection after obtaining image data returned by a robot in real time; carrying out line extraction on the image obtained in the previous step by utilizing a probability Hough transformation algorithm; and finally, classifying the detected lines into four kinds by utilizing the K-means algorithm according to the slope, calculating the mean value of the midpoints of each cluster of lines, then, establishing four lines to replace the lines detected in the previous step by utilizing the slope obtained by cluster and the midpoint mean values, dividing the four lines into two groups randomly, calculating the intersection point respectively, and taking the midpoint of the intersection point as a vanishing point. The method can rapidly detect the position of the vanishing point, and then, the heading direction of the robot is corrected by utilizing the vanishing point, so that the navigation of the robot can be realized. Compared with the conventional vanishing point detection method, the vanishing point rapid detection algorithm in the invention has the advantages of being simple and efficient, good in real-time performance and high in stability.

The invention discloses a floating type multi-floater wave power generation device which comprises a floating type structure, a mooring system, a hydraulic transmission system and a power generation system. The floating type structure floats on the sea surface and is moored through the mooring system. Multiple floaters of the floating type structure are connected with a main floating body through swing arms respectively. The floaters move along with waves and resonate together with waves, the floaters which do the floating and sinking movement after being excited by waves drive the swing arms to swing around a fixed fulcrum, a piston rod of a hydraulic cylinder is driven to reciprocate, an oily medium in the hydraulic cylinder is pushed to enter a hydraulic system to form a circuit and to enter a hydraulic motor, the hydraulic motor rotates to drive an electric generator to generate electricity, and then power generation is achieved through wave energy. According to the floating type multi-floater wave power generation device, the multiple floaters which move up and down along with waves absorb sea wave energy, stability of the main floating body of the device in waves is improved through a damping type base plate and the mooring system which adopts the three-point horizontal mooring method, and the floating type multi-floater wave power generation device has the advantages of being high in conversion efficiency, stability and reliability.

The invention relates to a preparation method of a water quality stabilizing agent. The water quality stabilizing agent prepared with the method is mainly compounded by using polycarboxylic acid, organic phosphonic acid compound, phosphine carboxylic acid compound, sulphonate compound, zinc salt, and the like. The agent has the advantages of high efficiency, low toxicity, and long-time storage. The compounding method and application method are simple and practical. The agent is suitable for corrosion prevention and scale prevention of circulating cooling water systems of petrochemical enterprises. A carbon steel corrosion rate can reach 0.010mm / a, and a scale inhibition rate can reach 95.30%.

The invention relates to real-time data acquisition technology, in particular to a distributed, networking and expandable Ethernet data acquisition and transmission method and a distributed, networking and expandable Ethernet data acquisition and transmission system which acquire and transmit data in real time and are based on Ethernet and programmable controller PLC technology. The Ethernet data acquisition and transmission system takes a programmable controller as a control device for data acquisition and communication, is provided with an Ethernet controller, is in Ethernet communication with a host computer by adoption of an Ethernet / IP communication mode and a Modbus transport protocol, and also comprises an I / O module which is connected with the Ethernet controller and connected with a terminal module through a final level digital quantity output module; and the programmable controller receives digital quantity signals or analog quantity signals from a sensor through the I / O module, is communicated with the host computer through a system program, selects a working model, and transmits the digital quantity signals or the analog quantity signals to a controlled device. The Ethernet data acquisition and transmission system has strong communication ability, wide application scope and a plurality of acquisition points, and a data acquisition system capable of being suitable for complex operating condition requirements is an urgent requirement of industrial fields.

The invention discloses an indoor robot positioning and environment modeling method based on UWB (ultra-wide band) and multiple sensors. The method is characterized in that a UWB label transmits pulse data packets formed by ultra-wide-band pulses to UWB receivers, the UWB receivers transmits the time differences of the pulse data packets reaching the receivers to a central processing unit through a switch, and the central processing unit preliminarily determine the position of the UWB label through a trilateral weighted centroid algorithm; an electronic compass collects the current course angle information of the robot, ultrasonic sensors collect currently-returned ultrasonic signals, and the central processing unit acquires the position information of obstacles according to the signals collected by the ultrasonic sensors and a Kalman filtering algorithm and update an environment map; the central processing unit fuses the preliminarily determined position of the UWB label, the current course angle information and the position information of the obstacles according to a double-layer Kalman filtering algorithm to obtain the precise current pose information of the robot. By the method, positioning precision, instantaneity and stability are increased.

The invention discloses a method for producing a compound microbial preparation serving as fodder, which comprises the steps of microbial inoculum production, material proportioning, bacillus subtilis medium preparation, beer yeast medium preparation and lactobacillus plantarum medium preparation. According to the method, bacillus subtilis, beer yeast and lactobacillus plantarum are bred to form compound strains, so that the totality of the compound thalli is increased, and the advantages such as high strain survival rate, strong stability and the like are achieved; the compound thalli are mixed with ball-milling chaff, bran and oligoisomaltose in a proper proportion, and the optimum compounding proportion is formed for the preparation; good conditions are created for the formation of the internal environment of intestinal canals of livestock and poultry, the aerobic bacillus subtilis interacts with yeast to generate more nutrient substances, amylase, protease cellulose and the like; and meanwhile, oxygen in the intestinal canals of livestock and poultry can be consumed, excellent growth environment is created for propagation of lactic acid bacteria, intestinal canal functions of livestock and poultry are improved, the fodder conversion rate is improved, and the microecological balance of the intestinal canals of livestock and poultry is improved.

The invention belongs to the field of soft magnetic ferrite, and particularly discloses a material for high superposition of a manganese-zinc ferrite core and a preparation method thereof. The material for the high superposition of the manganese-zinc ferrite core comprises the following main components in mol percentage: 53-54mol% of Fe2O3, 37.5-38.5mol% of MnO and 8-10mol% of ZnO. The invention further provides a preparation method of the material for the high superposition of the manganese-zinc ferrite core. By sintering through secondary reduction in a tunnel kiln, the density of the manganese-zinc ferrite core can be up to 4.9g / cm<3>. By adopting the material provided by the invention, the superposition and the inductance of the manganese-zinc ferrite core can be improved, the work efficiency of the can be improved, the production cost can be reduced, and the miniaturization and the high-efficiency operation of the transformer can be realized.

A protonated g-C3N4 / BiOBr heterojunction photocatalyst is flower-like particles consisting of flower-like BiOBr and flaky g-C3N4 growing on the flow-like BiOBr in situ. The photocatalyst is prepared with the following method: 1) calcining a precursor of g-C3N4 in air to obtain g-C3N4 photocatalyst particles; 2) dispersing the g-C3N4 photocatalyst particles in a hydrochloric acid solution, stirringthe solution at the normal temperature, and washing the g-C3N4 photocatalyst particles with deionized water to be neutral; 3) drying the g-C3N4 photocatalyst particles in the step 2 to obtain a protonated g-C3N4 photocatalyst; 4) dissolving the protonated g-C3N4 photocatalyst and bismuth nitrate in water, adding an acetate solution after stirring, adding potassium bromide and sodium acetate afterstirring at the room temperature, conducting an aging reaction after stirring, washing an obtained precipitate with water and absolute ethyl alcohol respectively, and then, performing centrifugationand drying to obtain the protonated g-C3N4 / BiOBr heterojunction photocatalyst. The invention further discloses a preparation method of the catalyst.

The invention discloses an elder fall-down intelligent detection and positioning active and passive alarm system and method, and mainly solves the problems in the prior art that detection efficiency and accuracy are low and automatic alarm cannot be performed. The system comprises an elder fall-down detection module (1), a cloud server (2) and a client side (3). The elder fall-down detection module (1) is arranged at the waist part of an elder to acquire state data including position information and safety information and intermittently transmit the state data to the cloud server (2) or transmit the state data to the client side (3) in a point-to-point way. The cloud server receives the state data of the elder fall-down detector to store in a database and transmits the state data to the corresponding client side according to the control command of the client side. The client side transmits the control command to the cloud server or the elder fall-down detector and receives and processes the feedback state data. The success rate of fall-down detection is high, automatic alarm can be performed and short messages and a data network can be simultaneously used for communication so that stability is high, and the system and the method can be used for solving elder lost and fall-down rescue.

The invention discloses a competitive bidding simulation system and method based on a multi-agent and multi-electricity market model. The invention is characterized in that the system comprises the following four layers (six modules): a user interface layer comprising a graphical user interface (GUI) module, a control logic layer comprising a Server module and a Remote module, a simulation logic layer comprising an ISO module and a GenCo module, and a data information layer comprising a database module. The simulation method comprises the following steps: 1) as the system is started up, establishing a Server Agent module, and entering into a waiting state; 2) inputting a task enabling the system to enter into simulation through the GUI module by a system administrator; 3) starting up the simulation task; and 4) processing simulation data, thus finishing one simulation case. The invention ensures that the existing actual requirements on electricity market simulation are met, and higher system stability can be provided.

The invention is suitable for the field of data synchronization, and provides a data synchronization method and a data synchronization firmware platform. The method comprises the following steps of monitoring on-line states of databases, wherein different databases may be located in different networks; receiving device positioning information uploaded by an on-line database, and transmitting the device positioning information to a background management terminal to be displayed; remotely receiving a set synchronization mechanism and synchronization configuration information, which are sent by the background management terminal; according to the synchronization mechanism, receiving data uploaded by a source database, and outputting the data to a target database after performing format conversion. The invention is a synchronization system platform which may be used among a plurality of database platforms and also may be used for database remote backup; just by simply setting a connection between the source database and the target database and setting corresponding synchronization mechanism, data synchronization between two databases can be realized; works of data extraction and resource information acquisition are realized conveniently; and the method and the platform provided by the invention are suitable for the work environments, such as data hot standby, data extraction and resource integration.

A carbonatite oil well density selectivity water shutoff agent comprises, by weight, 100 parts of cement, 60-75 parts of coal ash, 50-58 parts of clay, 52-62 parts of micro silicon, 5-8 parts of early strength agents, 16-28 parts of fluid loss agents and 1100-1200 parts of water. A preparation process of the carbonatite oil well density selectivity water shutoff agent includes: weighing the fluid loss agents and the early strength agents according to the formula ratio, dissolving the weighed fluid loss agents and the weighed early strength agents into the water obtained according to the formula ratio, and then adding the cement, the coal ash, the clay and the micro silicon according to the formula ratio so as to obtain the carbonatite oil well density selectivity water shutoff agent. The carbonatite oil well density selectivity water shutoff agent has the advantages of capability of staying among oil-water interfaces to set up a water shutoff partition, guarantee of solidification effects, safety in injection, expansion of shutoff radius, high compression strength after solidification, easiness to prepare, good injection performance, simplicity in construction process and high construction efficiency.

The invention discloses a preparation process of a beta-carotene nano-emulsion. An aqueous phase material and an oil phase material are well dissolved and then discharged at the same time, the flows of an aqueous phase and an oil phase are respectively controlled instantaneously, and a pipeline shearing machine is used to mix, shear, emulsify and homogenize online to obtain the nano-emulsion. Due to the preparation process, each area of the materials is evenly mixed, the average grain size of the emulsion is less than 100 nm and is even, the distribution of the grain size is narrower, the stability is stronger, and the problems of poor stability and high probability of layering of the common emulsion are overcome in use. The production process uses no organic solvent, so that the safety is higher; moreover, the provided production process can continuously produce, so that the production efficiency is greatly improved.

The invention discloses a partially hydrolyzed acrylamide water-soluble polymer with an utlralong hydrophobic long chain, a preparation method therefor and an application thereof. A structural formula of the partially hydrolyzed acrylamide water-soluble polymer is as shown in formula II. The preparation method for the polymer as shown in formula II provided by the invention comprises the following steps: (1) under an inert atmosphere, dissolving acrylamide and docosyl polyoxyethylene ether methacrylate into water to obtain a solution I; (2) under the inert atmosphere, dissolving acrylic acid into water to obtain a solution II, and adding NaOH into the solution II to regulate the pH value of the system to 6-7; and (3) mixing solutions I and II obtained in the steps (1) and (2), and adding an initiator into the mixed solution to carry out a polymerization reaction, thereby obtaining the polymer. According to the preparation method provided by the invention, raw materials are easily available, preparation is simple, yield is relatively high, use is safe and storage is convenient. The partially hydrolyzed acrylamide water-soluble polymer with the utlralong hydrophobic long chain can be directly used, and has an extensive potential utilization value in the fields of oil exploitation, paint, medicines, daily use chemicals and the like.

The invention provides a fluorescent two-dimensional code security identification method based on nano particles, which comprises the following steps: establishing a security database; taking a picture of a sample under test; and extracting an identification code in the picture of the sample under test, and comparing the identification code in the picture of the sample under test with the information in the security database to get a security identification result. The establishment of the security database includes the following steps: preparing a fluorescent material; making a security substrate; making a security pattern; taking a security picture; extracting feature information; and carrying out encoding and storage. The method has the following beneficial effects: as the distribution of the fluorescent material on the substrate is completely random, the security pattern cannot be copied; full-automatic modeling and anti-counterfeiting is realized; as long as a picture of a sample is input, a security identification result can be obtained through real-time analysis; and the up-conversion fluorescent material is very stable and does not fade at high temperature so that a security sample can be preserved for a long time and is not easy to lose effectiveness.

The invention relates to a method for deleting spectral lines of handwritten music scores of U-net and ResNet, and comprises the following steps: the U-net and the ResNet are combined to construct a deep learning network structure, and a model suitable for deleting the spectral line of the handwritten music score is established; wherein the input of the deep learning network is an original music score image, the true value label is a corresponding no-spectral-line music score image, the output of the deep learning network is a result image containing a probability value, a final threshold value is set according to specific data, binarization operation can be completed on the result image, and a final result is obtained; data enhancement; and training the model: training the constructed model by using the images of the training set, and carrying out parameter fine tuning according to the data of the verification set to obtain the optimal model parameters.

The invention provides a high-stability oil-based polymer powder suspension. The high-stability oil-based polymer powder suspension is prepared from a weighting agent, a stabilizer, a surfactant, a cosolvent, polymer powder and base oil, wherein the weighting agent is a high-density organic solvent; the stabilizer is one of fumed silica and gas-phase aluminum oxide; the surfactant is one or two of naphthenic soap, Span 80, Tween 80, oleic acid, octylphenol polyoxyethylene ether and glyceryl triabietate; the cosolvent is one of methanol, urea and ethylene glycol monobutyl ether; the polymer powder is a water-soluble polymer; the base oil is an organic solvent. The defect that the stability of conventional polymer powder suspension is poor is overcome, and the high-stability oil-based polymer powder suspension can keep stable at the room temperature within 180 days and also has the advantages of high solid phase content and low viscosity.

The invention discloses a compound membrane bioreactor for treating tuber mustard waste water, which is an integrated reactor formed by combining a biomembrane process and active sludge process combined compound bioreaction area and membrane separation. The reactor consists of a membrane suspending area, a membrane piece area, a water feeding system, an aeration system, a water discharge system and self-control equipment. Attached growth biomembrane and suspended active sludge, which are two coexisting microorganisms, cooperate to remove the pollutants from the tuber mustard waste water; and the purified waste water is subjected to sludge and water separation by a membrane and is discharged after reaching standards. The sludge expansion in a salt-containing waste water active sludge treatment process is inhibited by means of filling a filler in the bioreaction area and using the membrane separation component in place of the conventional biological treatment. The reactor has the characteristics that: the microorganism concentration is high; the population structure is diversified; the food chain is long; the impact load resistance is high; the treatment organic load is high; the biological nitrogen and phosphor removal capacity is high; membrane pollution can be relieved and can be controlled easily; the quality of effluent is high; the project investment and operation cost arelow; and the like.

The invention relates to a metal complex MXY(L) and a method for hydrogenation reduction preparation of alcohol from carbonyl compounds containing ketone, esters and the like by using the complex as a catalyst. In the MXY(L), M is selected from metals Fe, Ru, Os, Co, Rh, Ir and other transition metals; X and Y may be the same or different anionic ligands; L is a tetradentate ligand containing -NH- pyridyl and two heteroatoms. The complex disclosed by the invention has the advantages of being high in catalytic activity, strong in stability and the like.

The invention relates to a fiber gas sensor based on Fourier transform spectrometry, which is characterized in that a light source is connected with a fiber polarization splitter by a single mode fiber, and the single mode fiber led out from the fiber polarization splitter is respectively connected with the first ports of two same fiber circulators; the second ports of two fiber circulators are connected with two input ends of a sensing head via the single mode fiber; the third ports of two fiber circulators are connected with two single mode fibers with the same length; the receiving surface of the photoelectric detector is parallel to the plane formed by two output ends; and the output end of the photoelectric detector is connected with a signal processing system. By adopting a broad band light source, the invention can obtain bigger radiant flux, simultaneously records all spectrum components, has larger luminous energy output as well as bigger sensitivity and signal-to-noise ratio, lowers requirements to the light source and does not need to know the specific components and absorption peak position of gas to be measured, thus the fiber gas sensor has higher popularity.

The invention relates to a preparation method of a high-molecular polymer crack filler for pavements. The high-molecular polymer crack filler for pavements is prepared from the following raw materials in percentage by weight: 65-72% of 70# or 90# straight-run asphalt, 15-20% of SBS (styrene-butadiene-styrene), 8-15% of compatilizer and 0.5-1% of stabilizer. The preparation method comprises the following steps: 1) heating the straight-run asphalt to 170-175 DEG C, adding the SBS and compatilizer, stirring for 1-2 hours, and keeping the temperature for 1 hour; 2) adding the stabilizer, starting a colloid mill, and stirring for 15-30 minutes; 3) sending into a development tank, cooling to 105-120, and developing for 1-2 hours; and 4) discharging, and packaging. The compatibility between the asphalt and high-molecular polymer is enhanced by regulating the raw material proportion and selecting the optimal compatilizer; and the prepared high-molecular polymer crack filler for pavements has the advantages of high stability, high low-temperature elongation percentage and high binding strength with pavements.

The invention discloses an EGCG chitosan / beta-lactoglobulin composite nanoparticle. The EGCG chitosan / beta-lactoglobulin composite nanoparticle is characterized by being prepared from EGCG, chitosan and beta-lactoglobulin at the mass ratio of 1 to (3-6) to (1-3); the chitosan is selected from a mixture of carboxymethyl chitosan and chitosan hydrochloride at the mass ratio of 1 to (1-1.5); the particle size range of the composite nanoparticle is 100-300nm; and Zeta potential is 20-30mV. The chitosan / beta-lactoglobulin composite nanoparticle coated with the EGCG is prepared from the carboxymethyl chitosan, the chitosan hydrochloride and the beta-lactoglobulin. A core-shell composite nanoparticle structure for transporting the EGCG is formed by crosslinking and assembling of the beta-lactoglobulin and the chitosan subjected to heat treatment. The chitosan / beta-lactoglobulin composite nanoparticle is capable of avoiding degradation of acid and enzyme in a body, has high stability, and has certain targeting and slow-release properties; the problem that an existing chitosan-sodium tripolyphosphate nanoparticle is easily degraded by gastric acid as an oral delivery carrier is solved; and the bioavailable efficiency of oral absorption of the EGCG is improved.

The invention relates to hotpressed or embossed artificial leather, which comprises a surface layer, a foaming layer and a base cloth layer in sequential arrangement, wherein the surface layer is a polyurethane surface layer; the polyurethane surface layer is prepared from the following preparation raw materials in parts by weight: 95 to 105 parts of polyurethane resin, 0.1 to 0.3 part of flattingagents, 15 parts of antiaging agents, 1 to 10 parts of coloring agents and 100 parts of compound organic solvents. The invention also relates to a preparation method of the hotpressed or embossed artificial leather. The hotpressed or embossed artificial leather has the advantage that the hand feeling and the exquisite feeling of the leather after the stamping are improved.