166results about How to "Strong simulation" patented technology

An online game is provided in which game participants select videos to play to other game participants. The game presents a virtual social venue including a virtual video screen positioned in front of a virtual audience. The virtual audience is populated with representations of game participants visible to all, creating the ambience of a live event. Mechanisms are provided to incentivize the selection of entertaining and captivating videos. Game participants register their approval or disapproval of the video content through a social feedback tool. The game interface monitors the collective feedback of game participants and simulates a crowd response consistent with the participants' feedback.

Disclosed are an automatic three-phase unbalanced load compensation experimental device and its control method. The experimental device comprises an automatic compensation device, a load simulation part, and detection, display and control parts. The automatic compensation device comprises power capacitors and intelligent grouping compound switches; the detection, display and control part comprises current transformers, molded case circuit breakers, a three-phase digital display ammeter, a three-phase electric power monitoring instrument, a protocol conversion module, 485 buses, Ethernet cables and an upper computer; the load simulation part comprises phase A, B and C loads which are in star connection and are same in component and circuit connection, an analog output module and a relay output module. Power monitoring instrument and digital ammeter are connected to the grid by circuit breaker and current transformer. The automatic compensation device and load simulation part are connected to the grid in parallel.

The invention provides a double safety and effectiveness inspection method of human lumbar bone and implant, and belongs to the field of medicine. The method comprises the following steps: acquiring a 3D (three-dimensional) rendering model of lumbar body bone, lumbar disc and interspinous ligament by a 3D reconstruction technology; performing 3D grid division to the 3D rendering model, and giving attributes of a heterogeneous material to the 3D rendering model; performing 3D modeling to an implant; assembling the lumbar body bone, the lumbar disc, the interspinous ligament and the implant, and analyzing stress and strain of the assembly by adopting uniformly distributed nodal load through a finite element analysis method; simulating visible finite element analysis by a computer before the implant is implanted into a human body. Therefore, the verification requirement to bone and implant double safety and effectiveness can be fulfilled, the damage of the implant to original human lumbar bones can be prevented, double safety and effectiveness of the bones and implant can be guaranteed, the manufacture cost can be effectively reduced along with convenience and quickness, and individual and industrial manufacturing of a human lumbar bone implant can be realized. The method is applicable in the field of implant stress-strain analysis in the orthopedics department.

The invention discloses a three-dimensional graphene / carbon nanotube network flexible multifunctional strain sensor preparation method. According to the invention, the three-dimensional network of three-dimensional graphene and a one-dimensional carbon nanotube grows through two-step chemical vapor deposition; and the three-dimensional network and an elastic polymer as a flexible substrate are solidified and combined to acquire a flexible wearable multifunctional electronic strain sensor based on the three-dimensional network of the graphene and the carbon nanotube. According to the invention, the electronic strain sensor breaks the limitation relationship between the strainability and the sensitivity of the strain sensor, has an excellent electronic strain sensing performance and the function of a micro heater, realizes high sensitivity detection of human physiological signals and physical activities, shows excellent electronic skin simulation capabilities and a micro heating source application performance, has the advantage of simple process, and can be widely used in many fields such as clinical diagnosis, health monitoring, a robot, an electronic screen, electronic skin, a flexible micro heater and intelligent home.

The invention relates to a preparation method for a dry-type water colored sliver, comprising following technical steps: 1) preparation of polyurethane modification acrylic acid latex: dihydric alcohol is put into a reactor and then temperature is increased to 70 DEG C to 100 DEG C, then dihydric alcohol and organic tin dihydric alcohol is added and temperature is increased to 100 DEG C + / - 5 DEG C for 2 to 4 hour reaction, then temperature is decreased to 60 DEG C + / - 5 DEG C and methyl acrylate and dihydroxy methylpropanoic acid are added, then circumfluence temperature is controlled at 60 DEG C to 80 DEG C and reaction is carried out for 6 hours + / - 0.5 hours; when NCO value in reaction system is lower than 1, prepolymer is transferred into a dispersator and is dispersed in water dissolved in neutralizing agent of triethylamine, then water polyurethane is prepared; 50 to 100 pieces of water polyurethane are put into a reactor, temperature is increased to 70 DEG C to 90 DEG C and polyurethane modification acrylic acid co polymerization latex is obtained: step 2, the preparation of dry-type water colored sliver. The dry-type water colored sliver of the invention has the advantages of fine climate resistance performance, no conglutination on the way of transportation, fine elasticity, no discharging of organic matter with volatility and cost saving.

The invention discloses a texture replacing method based on a two dimension image; the method comprises the following steps: calculating each chartlet according to model UV; fusing model normal with texture normal; simulating real photosensitive lines; fusing texture diffuse reflection information; fusing texture highlight information; fusing texture color information; integrally fusing all calculated component including fused color information, diffuse reflection information and highlight information, thus obtaining the replaced texture effect.

The invention belongs to the technical field of oil-gas development laboratory simulation experiment facilities and evaluation, and particularly relates to a rock core gas / liquid dual-purpose permeability testing device and a reservoir damage evaluation method. The testing device at least comprises a gas-driven sampling device, a visible rock core holder and a gas flowmeter, wherein the gas-driven sampling device comprises a gas-driven gas inlet module and a gas-driven liquid inlet module; the visible rock core holder comprises an inlet end, an outlet end, a first plug body and a second plug body; and the gas flowmeter communicates with a gas outlet pipeline. The method respectively detects the rock core gas permeability K1 and rock core gas permeability K2 subjected to pollution damage by using the device, and calculates the permeability recovery ratio and permeability damage ratio. The technical scheme provided by the invention can simultaneously test the gas permeability and liquid flow permeability of the rock core as well as the permeability recovery degree of the rock core under the pollution of the working fluid. The testing device has the advantages of high simulation degree, ingenious connection, simple structure, high stability and high durability, and is convenient to operate.

The invention relates to a manufacturing method for a combined ceramic tile with a complete pattern, which is spliced by a plurality of ceramic tiles. The method comprises the following steps of: mixing raw materials to prepare a powder material, pressing the powder material to obtain green tiles, carrying out printing and glaze spraying on the green tiles, sintering the obtained tiles to obtain the ceramic tiles, and performing seamless splicing on the plurality of ceramic tiles with different or identical figures to obtain the combined ceramic tile with the complete pattern. Compared with the prior art, the combined ceramic tile can fully display the real effect of natural stones by means of large format splicing, is strong in three-dimensional effect and rich in layering, can better adapt to current market trend, and is grand and very impressive after being paved.

The invention discloses an infrared heating testing device and testing method for bituminous pavement, and aims to enable the measured test data conclusion to play a theoretical guiding function on practice, and further enable the accuracy to be high, the simulation performance to be high and operation to be simple; the infrared heating testing device comprises a test bed framework, wherein an infrared ray generation device is arranged on the test bed framework; the infrared ray generation device is connected with an infrared ray generation controller, a liquefied petroleum gas inlet control valve and a variable-frequency air blower; the liquefied petroleum gas inlet control valve is connected to a liquefied petroleum gas source; the variable-frequency air blower is connected with an air source; a test block tray used for placement of a pitch test block is arranged at the lower end of the infrared ray generation device; an infrared radiation flow sensor capable of collecting the infrared ray radiation quantity of the infrared ray generation device is arranged on the test block tray; a plurality of temperature sensors are arranged in the pitch test block during testing; the infrared radiation flow sensor and the temperature sensors are all connected to a data acquisition instrument; the data acquisition instrument is connected to a computer capable of displaying test data.

The invention provides a method and device for performing vegetation parameter remote sensing retrieval in a neural network system. The method comprises the steps as follows: training data sets between vegetation parameters and earth surface reflectance of different types of earth surfaces are obtained according to simulation models of earth surface reflectance of different types of earth surfaces; a neutral network between the vegetation parameters and earth surface reflectance of different types of earth surfaces is established; training data sets between earth surface reflectance and apparent reflectance under different meteorological conditions are obtained according to atmospheric radiation models; a neutral network between the earth surface reflectance and the apparent reflectance under different atmospheric conditions is established; multiple neutral networks are combined to form a neural network system; and remote sensing data obtained after radiometric calibration or atmospheric correction is subjected to vegetation parameter remote sensing retrieval in the neural network system. According to the method and the device, multiple different neutral networks can be combined to form the neural network system, compared with the prior art, the data analog capability is stronger, and an obtained result is more accurate.

The invention discloses a multi-atmosphere dynamic thermogravimetric-differential thermal analyzer which belongs to the field of petroleum refining industry and researches application thereof in sulfur transfer performance simulation and evaluation of flue gas. The analyzer comprises a protection gas circuit, a multigroup reaction gas circuit, a purging gas circuit, a switching valve, a test reactor, a drain port, a tail gas absorption device and an electrothermal furnace. The analyzer can blend and provide different required multicomponent mixed gas through one or a plurality of groups of gas regulating and mixing systems, switch the atmospheres in the test reactor according to requirements, simulate reaction atmospheres with complicated changes, realize dynamic in-situ testing, more particularly simulate a sulfur dioxide atmosphere and a hydrogen atmosphere (or a hydrocarbon atmosphere) under the micro positive pressure and carry out safe switching between the sulfur dioxide atmosphere and the hydrogen atmosphere (or the hydrocarbon atmosphere), record changes of the weight and the temperature of a sample in thermal treatment process at the real time under the condition of programmed temperature controlling, carry out thermogravimetric analysis and differential thermal analysis and is used for simulating and evaluating the performance of a sulfur transfer agent of catalytically-cracked flue gas.

The invention relates to bait formed by novel polymer materials and a production method thereof. Natural food auxiliary materials, sesame powder, butter, sweetening agents, amylase, blending agents, emulsifying agents, plasticizer, attractant, preservatives and coloring agents are added to basic matrix prescription materials which are utilized as basic raw materials to form the bait. The production method comprises mixing and heating polyvinyl alcohol and hydroxypropyl methyl cellulose to 135 DEG C, reacting for 20 to 30 minutes and placing the polyvinyl alcohol and the hydroxypropyl methyl cellulose as A at the room temperature for stand-by; heating a suitable amount of water to 40 to 50 DEG C under the revolving speed of 40 revolutions per minute to dissolve gelatin and adding and heating sodium chloride, sucrose, glycerinum, microcrystalline cellulose, carbomer and sodium carboxymethyl cellulose to 65 DEG C; adding fish protein concentrate, glycine, shrimp powder, pigments, disintegrating agents and the preservatives under the revolving speed of 40 revolutions per minute, lasting the temperature at 65 DEG C for about 5 minutes, mixing with the A, placing the mixture at the room temperature and adding the attractant, micro capsules with the wrapped attractant or bionic fish visceral small strip dosage forms.

The invention discloses a bituminous mixture heat conduction testing device. The bituminous mixture heat conduction testing device comprises a testing box, a polyurethane foam heat insulating layer, constant temperature circulating water boxes, a heating plate, a temperature data collecting instrument, a computer and an intelligent constant temperature circulator, wherein the polyurethane foam heat insulating layer is paved on the inner wall of the testing box; the testing box is internally provided with the two constant temperature circulating water boxes, and the heating plate is arranged between the two constant temperature circulating water boxes and is connected with a temperature controller; a testing test specimen is arranged between the heating plate and each constant temperature circulating water box, the testing test specimens are provided with temperature sensors connected with the temperature data collecting instrument, and the temperature data collecting instrument is connected with the computer for displaying data. The bituminous mixture heat conduction testing device disclosed by the invention has the advantages that polyurethane heat insulating foam is utilized to control the side heat of the test specimens, the loss of the side heat is reduced, and the testing accuracy is improved; the constant temperature circulator enables the temperatures of the surfaces of the inner sides of the test specimens to be uniform, a uniform heat exchange requirement is achieved, and the uniform constant temperature of the outer sides of the testing test specimens is realized, so that the testing accuracy is improved; the simulation property is strong, the operation is easy, and the testing device can be utilized to obtain a heat conductivity coefficient of a bituminous mixture.

The invention relates to a virtual car crash detecting system and a construction method thereof. The construction method comprises the following steps: constructing a car geometrical entity model according to car total quality, total size, car type base information and the external dimension of parts; constructing a finite element model of a dummy man; respectively constructing a safety belt, a safe air bag and a barrier model; constructing a virtual emulation and calculation testing table; transferring various original models in a virtual testing field to construct a virtual testing field; transferring various virtual models to be presented in a virtual environment; defining collision experimental conditions; and starting a simulation test. The virtual car crash detecting system has short development period, low use cost and realer test result.

A processing method of vacuum forming for leather products comprises: step 1, making mold; step 2, heating raw materials of the leather products to a specified temperature, putting on surface of the mold, staying in vacuum forming conditions, and forming patterns on surfaces of the raw materials of the leather products, the patterns being corresponding to those on the surface of the mold; and step 3, cooling the raw materials of the leather products, and molding into the leather products for later use, wherein the specified temperature is 150-200 DEG C, the vacuum forming conditions are a vacuum degree range between 350-700 mmHg. According to the invention, the method is simple in technology, molds are convenient to prepare, products can be molded for one time, simulation of finished products is strong, and production efficiency is high.

The invention discloses a nuclear power VR (virtual reality) image simulation system and a nuclear power VR image simulation method. The nuclear power VR image simulation system comprises a VR helmet display system, a nuclear power scene simulation system, a haptic manipulation system and a motion sensing system. The nuclear power VR image simulation method comprises the following steps: 1) defining functional requirement of nuclear power VR image simulation; 2) establishing a hardware system for the nuclear power VR image simulation; 3) shooting and making a nuclear power VR image scene; 4) introducing the nuclear power VR image scene into the nuclear power scene simulation system; 5) performing data transmission and data debugging among the VR helmet display system, the nuclear power scene simulation system, the haptic manipulation system and the motion sensing system; 6) training the nuclear power VR image simulation system. Through the nuclear power VR image simulation system and the nuclear power VR image simulation method, operation, maintenance and accident handling of nuclear power equipment can be drilled.

Being applicable to apparatus in video game, simulated training, motion effect cinema, and the simulated vibrator includes shell, winding, and magnetic hammer. The shell supports winding. The magnetic hammer is installed in cavity of the shell. Through elastic piece, the magnetic hammer is connected to the shell body flexibly. End plates are installed on two ends of the shell body. When doing reciprocal motion, the magnetic hammer contacts end plates or vibration transmission pieces. Advantages are: directivity of vibration, high simulation capability, and obvious collision effect, vivid effect. When multiple simulated vibrators are utilized together can simulate most of vibration situation in reality.

The invention relates to a bamboo juice essence, which has the characteristics of sweet, fragrant, lasting and stable smell, strong simulation property, good taste and the like by taking natural bamboo leaf oil and bamboo juice extracts as main raw materials and spice made from natural equal components (ethyl butyrate, trans-2-hexenal, leaf alcohol, linalool, hexyl hexanoate and the like) with strong affinity to bamboo juice as an auxiliary material. In addition, the bamboo juice essence can be also used as an additive in fermented milk, drink and other foods so that the final products of the fermented milk, the drinks and the other foods have intense fruit juice taste, the natural fragrance and the taste of the bamboo juice can be provided to the products, and the heat resistance and the fragrance quality of the products are higher than the level of the similar essence in China.

The invention provides an embroidering method adopting coiled twist silk threads. In the method, embroidery needles and embroidery threads are utilized for embroidering on embroidery cloths. The method is characterized in that the embroidery threads are twist silk threads formed by twisting at least two strands of silk threads in the forward direction and stranding the folded threads of the twisted silk threads in the backward direction; and during embroidering, the twist silk threads are firstly coiled and arranged on the fronts of the embroidery cloths according to the textures of floral patterns, and then the embroidery needles and the embroidery threads are utilized to sew the coiled and arranged twist silk threads on the embroidery cloths, wherein the method of coiling and arranging is characterized by coiling or / and arranging the twist silk threads on the fronts of the embroidery cloths. The method has the following beneficial effects: the limit that only the embroidery needles are used to express the floral patterns in the traditional method is broken through; and as the third dimension and sense of reality are strong, the expression and render forces are obviously improved. Thus, the method is especially suitable for expressing the plaited articles such as straw plaited articles, rattan plaited articles, Chinese knots and the like.

The invention discloses a hybrid modeling method for a feeding system of a numerical control machine tool. The hybrid modeling method comprises a dynamic basic model and a neural network deviation model based on big data, wherein the dynamics basic model is obtained through dynamics theory analysis and parameter identification; the neural network deviation model is obtained by analyzing and training an instruction sequence, simulation prediction data of the dynamic basic model and actual response data; and the instruction sequence is input into a system mixing model, and the actual response sequence is predicted to obtain a mixed prediction sequence. Compared with a pure dynamic model, the technical scheme of the invention has the advantages that the simulation of a highly nonlinear process (such as a reverse process) is more accurate, and compared with a pure neural network model, the generalization ability under different processing technologies is stronger. Through a hybrid modelingmode, accurate simulation of a complex dynamic feeding system is realized.

This invention provides a process for preparing an emulated plastic composite, which belongs to the field of emulated plastics. In this invention, components including polyvinyl chloride paste resin and powdered rubber with diameters in the range of 30-200nm and a gel content higher than 60% are uniformly mixed and molded to obtain the emulated plastic composite. The starting components may also include a light-storing luminescent material, which can be one or several of the following light-storing luminescent materials: silicate system, aluminate system or sulfide system. The emulated plastic composite in this invention, which comprises 1-40 portions of the luminescent material and 2-8 portions of the powdered rubber, has a high strength, a high elasticity and a good sense of quality, and can be used to prepare a wide variety of bio-emulators.

The invention provides a large aircraft cockpit lighting environment simulation test system. The test system comprises a flying process cockpit light environment analog simulation subsystem, a cockpit light environment real-time recording subsystem and a cockpit lighting vision work efficiency test subsystem. The light environment analog simulation subsystem can simulate all-weather static and dynamic state light environment outside a cockpit in the flying process, the light environment real-time recording subsystem can be utilized for collecting environment light changes of all areas in the cockpit, and finally, a lighting vision work efficiency test subsystem is applied to assessing brightness uniformity, contrast and readability of all the areas of the cockpit. Compared with the prior art, the light environment simulation capability is high, the capacity of simulating the daybreak, dusk, thunderstorm, cloud penetration, noon light and other extreme light environments is achieved, meanwhile, the system has the light environment field collection and record functions, and the design problem of cockpit lighting is solved. Through the simulation test system, the dependency of the cockpit vision efficiency design on the aircraft test flight process can be eliminated, and in the cockpit lighting design stage, the effect verification of the lighting environment can be completed.

A quadruped walking machine capable of turning comprises a main body support, a quadruped walking mechanism, a turning mechanism, a transmission mechanism, a circuit control mechanism and an external packaging module. A single leg mechanism of the quadruped walking mechanism includes a support plate, a first link rod, a second link rod, a third link rod, a fourth link rod, a rotation shaft disc and a crank. The turning mechanism includes a front rotation platform, a rear rotation platform, a turning motor, a shaft coupling, a screw rod and a threaded pipe. The transmission mechanism includes a front transmission shaft, a rear transmission shaft, a front shaft, a rear shaft, a bevel gear, a universal joint, and a forwarding motor. The circuit control mechanism includes a control switch, a control circuit, and a limit switch. The inventive quadruped walking machine is high in control accuracy and wide in application, can walk forward by four feet and turn flexibly at the same time, provides bumpy experience and high simulation and entertainment effects, enables children to experience horse riding fun, and performs innovations on the movement form of an original walking toy on the market.

The invention discloses stone imitation paint and a production method. The stone imitation paint comprises raw materials, namely polyurethane, a glass fiber, an acrylic resin liquid, an elastic resinliquid, white quartz sand, natural colorful sand, water, a composite coupling agent, a leveling agent, a defoaming agent and an anti-settling agent. The stone imitation paint disclosed by the invention is diverse in color, sufficient in attractiveness and good in imitation property, and a constructed surface has the third-dimensional property and the multi-color decoration attractiveness, and haswaterproof anti-cracking properties, water and alkali resistance, weather resistance, water scrubbing resistance, anti-fouling properties, alga resistance and chemical resistance. In addition, the stone imitation paint is good in stone texture, good in waterproof and cracking resistance, relatively long in weather-resistant service life, vivid in color, relatively good in anti-fouling property, relatively simple and convenient to construct, relatively applicable to heat-preservation base materials, low in manufacturing cost, rich in color and specification, simple and easy to construct and excellent in anti-cracking waterproof property.

The invention relates to a badminton shuttle sucking / serving machine which comprises a framework, a shuttle barrel, a vacuumizing mechanism and a serving mechanism. The shuttle barrel, the vacuumizing mechanism and the serving mechanism are arranged on the framework, a collecting groove is formed in the framework, the shuttle barrel is arranged in the collecting groove, a shuttle sucking opening is formed in the bottom of the front end of the framework and directly faces one end of the shuttle barrel, the other end of the shuttle barrel is hermetically connected with the vacuumizing mechanism by a sucking pipe, the serving mechanism is arranged on the top of the framework, and a shuttle inlet which can be matched with the shuttle barrel is formed in the serving mechanism. The badminton shuttle sucking / serving machine has the advantages that a shuttle sucking mechanism and a serving structure are integrally combined with each other, accordingly, collected badminton shuttles can be quickly and conveniently arranged on the badminton shuttle sucking / serving machine, and the badminton shuttle sucking / serving machine is simple in structure and convenient to operate.

A high-temperature thermal field and complex atmosphere environment static coupling device includes a high-temperature atmosphere furnace, a gas circuit control unit and an exhaust gas excluder, the high-temperature atmosphere furnace comprises a heating chamber, the bottom of the heating chamber is provided with a gas inlet, the top of the heating chamber is provided with a gas outlet, the gas inlet of the heating chamber is connected with a gas outlet of the gas circuit control unit by a pipeline, the gas outlet of the heating chamber is connected with the exhaust gas excluder by a pipeline, the outer side of the high-temperature atmosphere furnace is provided with a weight measuring apparatus, a measuring end of the weight measuring apparatus is arranged in the heating chamber, the gas circuit control unit is connected with different gas storage high pressure gas cylinders by separate pipelines, each pipe is provided with a gas mass flow controller, the high-temperature thermal field and complex atmosphere environment static coupling device is simple and reliable in structure, easy to use and maintain, strong in atmosphere simulation capabilities, and high in use temperature, can be used for instant online measuring and recording of data, can be used for accurate and realistic simulation of aero-engine gas environment, chemical heat exchanger and other high-temperature and oxidation and corrosive atmosphere coexist actual working conditions.

The invention relates to the technical field of tools for medical teaching, in particular to a CT simulation system for teaching. The CT simulation system for teaching is suitable for teaching demonstration, free of radiation and harm, easy to operate and good in simulation effect and can simulate operation and output and display human body scanning information. The system comprises a simulation platform assembly, a simulation scanning frame assembly arranged outside the simulation platform assembly in a sleeving mode, a human body model arranged above the simulation platform assembly, a data storage and processing assembly used for receiving, processing and sending data, a control assembly and a display assembly, wherein the control assembly and the display assembly are connected with the data storage and processing assembly through cables. The CT simulation system for teaching has the advantages of being simple and reasonable in structure, low in manufacturing cost, suitable for purchase and use of schools, suitable for teaching demonstration, free of radiation and harm, easy to operate, good in simulation effect and capable of simulating operation and outputting and displaying the human body scanning information.

The invention relates to a plastic assembled engine model. A V type eight-cylinder automobile engine is taken as a simplified version, the structure is integral, the simulation is strong, an engine mount, a sump panel, a low crankcase, a crankshaft, a connecting rod, a connecting rod head, a piston pin, a piston, a cylinder seat, a cylinder top plate, a cylinder cover, a valve rod, a valve top, a crankshaft gear, a crankshaft belt pulley, a camshaft gear, a cam, a camshaft, a cam-pushed rocker, a rocker arm fixed seat, a rocker sleeve, a rocker arm, a rocker cover, a gear cover, a fan belt pulley, the crankshaft belt pulley, a fan, an exhaust pipe, a lower cover of the exhaust pipe, a gearbox housing, a top cover, a filter, a filter cover and other parts are made of plastic, the processing is labor-saving, the price is low, rust dirt caused by oil can be avoided, and the plastic assembled engine model is clean and sanitary; the working of a transmission mechanism constituted by the crankshaft, the connecting rod, the piston, a cylinder and the like is in line with the requirements of an actual product, so that the plastic assembled engine model is conductive to understanding the engine by trainees and improving mechanical knowledge; and the motor is used for driving the rotation in reverse direction, and the operation is safe and has no danger.

The invention relates to a composite artificial false fishing lure, and relative production. Wherein, said composite is formed by polycarbonate resin, polyethylene resin, acrylic nitrile- butadiene-styrene rein, added with silica dioxide nanometer powder; mixing and adding additive, injection molding, removing mould, cooling and shaping. The invention is lighter than wood production, with better flexibility and corrosion resistance, while it will not be degraded in long time service.