549results about How to "Meet actual use needs" patented technology

The invention relates to a method for preparing high heat-resisting polyethylene composite materials. The method takes advantage of the feature that thermosetting resin has sound rigidity and strength under high temperature after curing, and by adding reaction compatibilizing agent to act with thermosetting resin to form a semi-interpenetrating network of polyethylene and thermosetting resin, and thereby preparing novel polyethylene composite materials. The polyethylene, thermosetting resin, curing agent, accelerating agent, reaction compatibilizing agent and antioxidant which are premixed evenly in a high-speed agitator are added into a double screw extruder, and reactively blended at a proper temperature and rotation speed, the produced granules are extruded out, and the desired high heat-resisting polyethylene composite materials are achieved. Compared with the common polyethylene, the heat resistance and the strength of the materials under normal temperature and high temperature are improved remarkably, and the materials can be applied to the fields of civil buildings, auto parts, household electrical appliances as well as wires and cables, and the like.

The invention relates to a pose measure system of a cantilever type heading machine. The pose measure system comprises a laser pointing rangefinder and an optical goniometer. The pose measure system is characterized in that: the laser pointing rangefinder respectively emits a visible laser and an infrared ranging laser; the visible laser forms an image on a focal plane of a convex lens of the optical goniometer through the convex lens; a direction angle alpha<,> and a pitch angle beta<,> of a optical axis of the optical goniometer relative to a laser beam are obtained through image point coordinates. Because a preset optical axis of the optical goniometer is parallel to a fuselage axis of the heading machine, the alpha<,> and the beta<,> are the direction angle and the pitch angle of the fuselage axis relative to the laser beam. A spinning angle gamma of the fuselage relative to a horizontal plane can be obtained through a tilt angle sensor installed parallel to a datum plane of the heading machine. Therefore, influence on measurements of the direction angle alpha<,> and the pitch angle beta<,> due to the spinning angle gamma is corrected so as to complete the measurements of the direction angle alpha<,> and the pitch angle beta of the heading machine relative to the laser beam, and the spinning angle gamma of the heading machine relative to the horizontal plane. With the present invention, a range between the fuselage of the heading machine and the laser pointing rangefinder can be obtained through the infrared ranging laser; a position coordinate of the heading machine can be obtained through combining the position coordinate of the laser pointing rangefinder and parameters of emission angle of the laser beam; tunnelling workload and other information can be obtained through system output data.

The invention discloses a composite automatic synchronous energy transfer equalization circuit and an equalization method for a series battery pack. The circuit comprises n composite two-way battery unit energy transfer equalization modules, a master control module and equalization buses, wherein the composite two-way battery unit energy transfer equalization modules are arranged according to the number of battery units in the series battery pack; n is more than or equal to 1; the composite two-way battery unit energy transfer equalization module corresponds to a battery module consisting of k battery units which are connected in series; k is more than 1; and the composite two-way battery unit energy transfer equalization module consists of a switch matrix, an equalization control module, a two-way direct current (DC)-DC module, k discharge equalization circuits and a mode control switch. The composite automatic synchronous energy transfer equalization circuit and the equalization method for the series battery pack are high in reliability, low in cost, small in volume, light in weight, functionally comprehensive and easy to manufacture and use in large scale, and can be applied in the fields of electric vehicles, rail transit, wind-driven power generation and the like by which the series battery pack and a series capacitor bank are required.

A geopolymer composite material for 3D printing and a preparation method and application thereof are disclosed. The geopolymer composite material comprises the following ingredients (by weight): 20-25% of water-quenched granulated blast furnace slag powder, 10-15% of ground steel slag, 0-5% of fly ash, 33-45% of tailings machine-made sand, 3-5% of a composite activator, 2.5-3% of a high-molecular polymer, 1-3% of a volume stabilizer, 1-2% of a thixotropic agent, 0.05-0.1% of an antifoaming agent and 13.9-12.45% of mixing water. The above ingredients are fully and uniformly stirred and then the mixture is subsequently pumped into a 3D printer for construction. The geopolymer composite material has good caking property, strong stability and has good pump-out morphology maintaining capability and bond property. Printed buildings have good morphology and volume stability, and houses and buildings have good overall stability and use security.

The invention discloses an optimum design method of a small harmonic reducer. The optimum design method includes the steps 1), determining calculating parameters required by the optimum design to obtain target parameters of the optimum design; 2), determining a data range of the calculating parameters and the target parameters to obtain a target parameter solution set in accordance with the data range; 3), subjecting the target parameters in the target parameter solution set which is in accordance with the data range to iterative loop filtering to obtain optimal target parameters; 4), according to the obtained optimal target parameters and the corresponding calculating parameters, calculating to obtain other processing and manufacturing parameters to perform optimum design and manufacturing of the small harmonic reducer. The small harmonic reducer comprises a rigid gear and a flexible wheel which are mutually matched and adopts a wave generator of a double-wave-cam structure; the processing and manufacturing parameters are obtained by the above optimum design method. By means of adding correction factors and performing optimum design adjustment upon key parameters, the small harmonic reducer which is high in structural strength, long in service life and capable of realizing processing and manufacturing is obtained.

The invention discloses a method and device used for monitoring a three-way catalyst in an engine exhaust system. The method comprises the steps that the excess air coefficient of the inlet end of the three-way catalyst is adjusted according to the operation parameters of an engine; the jumping time of output voltage of a sensor installed at the outlet end of the three-way catalyst is detected; the jumping time is compared with the preset nominal time to obtain a comparative result; and according to the comparative result, whether the three-way catalyst is removed or ages is judged, and accordingly monitoring of the three-way catalyst is achieved. The three-way catalyst can be monitored online in real time by actively adjusting the excess air coefficient of the inlet end of the three-way catalyst and detecting the jumping time of output voltage of the sensor installed at the outlet end of the three-way catalyst.

The invention relates to an inductance and ultrasound coupling-assisted method for direct laser deposition of a metal material, belongs to the field of additive manufacturing and relates to a coupledenergy field. The energy field is obtained by coupling an inductance temperature field and an ultrasonic wave field. A follow-up electromagnetic induction device is suspended right below a laser headthrough an induction coil, so that the coil moves along with the laser head to preheat and slowly cool a round area around a molten bath. A bottom ultrasonic device is fixed between a worktable and abase plate, and ultrasonic waves are conducted to the molten bath upward through the base plate to impact and stir the molten bath and a solid-liquid interface. The coupled energy field makes up defects that a single inductance temperature field has no stirring effect to the molten bath and a single ultrasonic wave field which is short in action time to the molten bath is not obvious in effect. Induction heating plays a preheating and slow cooling role to reduce a temperature gradient and to reduce a thermal stress. The temperature field improves the impacting and stirring efficiency to the molten bath effectively by alleviating the solidification rate of the molten bath. The coupled energy field can reduce defects of cracks and pores, so that the mechanical properties of a metal materialformed part are improved.

The invention provides a multi-unmanned aerial vehicle dynamic route planning method based on space and time collaboration. The problems of space anti-collision and time collaboration of multiple unmanned aerial vehicles are solved in comparison with a single-machine A* route planning algorithm in the process of solving a coordinated route. The method comprises the steps of considering anti-collision constraint, a pace-consistent planning process, time collaboration cost and providing suggested average flight rate in planning; the method has the advantages that a simpler calculation structureis provided, the calculation speed meets an actual use requirement, the optimal route cost can be met when the actual requirement is met by the solved speed through the parameter adjusting, the factors such as risks and flight time in the actual flight of the unmanned aerial vehicle are coordinated; and meanwhile, a coping mechanism for the suddenly-appearing area needing to be avoided is designedin the method, the method is more oriented to an actual application scene, and therefore, the availability of the multi-unmanned aerial vehicle collaborative dynamic route planning is improved.

The invention discloses a single-shaft mortar and high-viscosity fluid stirrer for an axial turbulent flow pattern multi-wire cutting machine, comprising a stirring shaft, a stirring assembly and a driving mechanism, wherein the stirring assembly comprises impellers and short flow diversion tubes, the impellers are used for driving a material to move up or down in an axial and spiral mode along the inner wall of a pot body of a stirring pot, the short flow diversion tubes are used for restricting the material flow direction to an axial movement along the axis of the stirring shaft when the material moves up or down in the axial and spiral mode, the impellers and the short flow division tubes are assembled into the stirring assembly which drives the material needed to be mixed and stirred to do an axial turbulent flow motion during stirring, the impellers are coaxially installed at the bottom end of the stirring shaft, the short flow division tubes are coaxially and fixedly sleeved at the outer sides of the impellers, and the stirring speed of the stirring shaft is 600-1500rmp. The single-shaft mortar and high-viscosity fluid stirrer has the advantages of simplicity in structure, high stirring capacity, small shearing force, high dispersing power and high effect, and can be used for solving the problem that silicon carbide is broken due to the shearing force during the high-speed stirring of various traditional stirrers. Moreover, a stuck phenomenon is difficult to generate.

The invention discloses an intelligent dynamic compaction machine. The intelligent dynamic compaction machine comprises a loader and a compaction mechanism connected with the loader, wherein a loader is provided with a fuel tank, a fuel pump and a radiator connected with the fuel tank, and an engine connected with the fuel pump; the compaction mechanism is provided with a frame, a fuel cylinder support plate connected with the frame and a fuel cylinder connected with the fuel cylinder support plate, a movable pulley is connected with the top of a piston rod of the fuel cylinder, a soft connector is wound on the movable pulley, one end of the soft connector is fixedly connected with the frame, the other end of the soft connector is connected with a compaction hammer; a compaction operation condition detection system is arranged on the frame, and the loader is furthermore provided with a hydraulic system connected with the fuel pump and an intelligent control system connected with the compaction operation condition detection system and the hydraulic system. The intelligent dynamic compaction machine has characteristics of reasonable design, convenience for use and operation, capability of intelligently continuously compacting, relatively large compaction powder, large compaction thickness and compaction infection depth, high intelligent degree, complete function, stability and reliability in operation, strong practicability and high popularization and application value.

The embodiments of the invention provide a data processing method and apparatus based on an intelligent television. The method comprises the following steps: obtaining gender information and age information by performing face identification on a user by use of a face identification software development kit (SDK) integrated into an operating system where the intelligent television is disposed; obtaining the gender information and the age information through an interface of the face identification DSK; and pushing data corresponding to the gender information and the age information in an application program. According to the embodiments of the invention, a face identification technology is integrated into the intelligent television, the application program on the intelligent television can push corresponding network resources to users of different genders and ages, the users do not have to manually search for the network resources, the intelligent television is more intelligent, and actual application demands of the different users are satisfied.

The invention provides a smart wearable electrocardiogram monitoring system. The system comprises an electrode patch, a miniature electrocardiogram equipment mainframe, a smart terminal and a big data system. The smart wearable electrocardiogram monitoring system is multifunctional, by means of the system, not only can continuous monitoring and recording of an electrocardiogram over 14 days be conducted, but also analysis and management of collected electrocardiogram data and alerting can be conducted, so that grasping of comprehensive situations of a patient is promoted, and the actual use requirements of a user are fully met.

The invention discloses an air conditioner unit mode switching control method and device and an air conditioner system. The air conditioner unit mode switching control method comprises the following steps that after an air conditioner unit runs for first preset time under the current running mode, the number of needed refrigeration compressors and the number of needed hot water compressors are judged; the next running mode of the air conditioner unit is obtained according to the number of the needed refrigeration compressors and the number of the needed hot water compressors; whether the next running mode is the same as the current running mode of the air conditioner unit or not is judged; if yes, the air conditioner unit is controlled to continue to run with the current running mode; if not, the air conditioner unit is controlled to be turned off for second preset time under the current running mode, and the next running mode is executed. By means of the method, the running modes of the air conditioner unit can be automatically switched, the corresponding running modes are started according to the needs, the actual using requirements of a user can be met better, the temperature set by the user can be reached more quickly, and the heat recycling efficiency is improved by judging the number of the needed compressors of the system while the air conditioner unit runs.

The invention belongs to the technical field of intelligent homes, and aims to solve the problem that the user experience is poor due to the fact that an existing water heater and a bathroom warmer cannot be adjusted in linkage and the indoor environment temperature does not correspond to the water temperature of the water heater and the temperature in the bathroom. Therefore, the invention provides a control method for an intelligent home system. The intelligent home system comprises the water heater and the bathroom warmer. The control method comprises the following steps that the indoor environment temperature is acquired, and selectively enabling the water heater to adjust the water temperature and enabling the bathroom warmer to adjust the bathroom temperature according to the indoorenvironment temperature. According to the control method for the intelligent home system, a user can be at the proper water temperature and the bathroom temperature during bathing at any time, and theuser does not need to actively adjust the water temperature and the bathroom temperature; in addition, the water temperature of the water heater and the temperature of the bathroom warmer in the bathroom are adjusted based on the indoor environment temperature, so that the user cannot feel uncomfortable due to too large temperature difference when the user enters the indoor from the bathroom after bathing, and the user experience is further improved.

The embodiment of the invention discloses a sticky fish egg hatching device, and relates to the field of aquaculture equipment. The hatching device comprises a hatching box, wherein the top of the hatching box is provided with a sealing cover; a water outlet is formed in the bottom of the hatching box; the sticky egg hatching device also comprises a spraying device, a support frame device and a plurality of fish egg loading devices; the spraying device, the support frame device and the plurality of fish egg loading devices are respectively arranged in the sticky fish egg hatching box; the support frame device comprises a center shaft and a plurality of hanging support frames; the center shaft is in vertical arrangement; the plurality of hanging support frames are radially arranged at the periphery of the center shaft at intervals; the hanging support frames are used for hanging the fish egg loading devices; the spraying device is used for spraying water mist on the fish egg loading devices. The sticky fish egg hatching device provided by the embodiment has the advantages that the fish egg loading devices are hung through the support frame device; each fish egg loading device is hung in a separated way; the problem of oxygen deficiency due to fish egg overlying can be effectively solved; the fish egg hatching rate is improved. Through the arrangement of a temperature control system, the fish egg hatching temperature and humidity can be effectively controlled; the fish egg hatching rate is further improved.

The invention discloses a network traffic prediction method and device, and the method comprises the steps: enabling the prediction device to obtain a prediction network flow sequence of a second timeperiod after a first time period according to all prediction models pre-stored in a historical network flow sequence training model library of exit gateway equipment in a first time period; and updating the prediction model of at least one sub-time period according to the actual network flow of at least one sub-time period in the second time period of which the network flow error value is greaterthan the preset threshold when judging that the predicted network flow sequence does not meet the expected target based on a comparison result between the actual network flow sequence in the second time period and the predicted network flow sequence. Through the mode, the prediction device can train the prediction model corresponding to the sub-time period according to the historical network flowcorresponding to different sub-time periods, so the accuracy of predicting the network flow of exit gateway equipment by the prediction device can be improved, and the actual use requirements of users and operators are met.

The invention discloses a biological full-degradable polylactic acid / plant fiber composite material as well as a preparation method and an application thereof. The biological full-degradable polylactic acid / plant fiber composite material is prepared from the following raw materials in percentage by weight: 50%-78% of polylactic acid, 20%-35% of a plant fiber, 1%-9% of biological epoxy compounds, 0.5%-4% of inorganic nanoparticles and 0.5%-2% of an assistant. The polylactic acid, the plant fiber and the biological epoxy compounds are all from renewable biomass, have biodegradation characteristics, and completely conform to the requirements of low-carbon, environment-friendly and sustained economic development. The composite material has excellent mechanical properties of high strength and high tenacity, and excellent hydrophobic property, can be prepared by fusing and extruding once; and the method is simple, easy to operate and suitable for industrialized production. In addition, the composite material disclosed by the invention can be applied to preparation of automobile components, can also be applied to the field of preparation of high-grade products such as polylactic acid infant feeding bottles and water glasses, and has a wide application prospect.

The invention provides a shared stage management system. The system comprises multiple mobile stages, a user terminal and a management server, wherein each of the mobile stages is provided with a first communication module and a positioning module, and each mobile stage acquires location information based on the positioning module arranged on the same mobile stage and uploads the acquired location information based on the first communication module arranged on the same mobile stage; the user terminal comprises a second communication module, and the user terminal sends an appointment request for using the mobile stages based on the second communication module; and the management server comprises an information management subsystem and an appointment management subsystem, the information management subsystem is used for managing each mobile stage according to the location information uploaded by the corresponding mobile stage, and the appointment management subsystem is used for receiving the appointment request sent by the user terminal, responding to the appointment request, selecting a target mobile stage from the mobile stages and pushing authorization information of using the target mobile stage to the user terminal.

The invention discloses a UDP (User Datagram Protocol) based matchable strategy data transmission method. Strategies such as the message transmission mode, the message compression strategy, the message retransmission times, the message timeout, the single package sending length, the sending window number and the active message delay which are required by the transmission are abstracted to form a strategy configuration file and the strategy information is read from the strategy configuration file and the strategy configuration is performed before the data transmission. When the used network transmission channel environment is changed, a user does not need to modify software codes again and only needs to modify part of the strategies in the strategy configuration file to meet the actual use demand, the data transmission can adapt to bandwidth and narrow-band channels and stable and high-delay channels, the point-to-point and point-to-multipoint data transmission can be implemented, and the software use is flexible and simple due to the facts that only a transmission strategy of a sending end need to be modified and the automatic strategy matching is achieved through a receiving end.

The invention discloses a method and a system for testing air-conditioning electric devices. The method comprises testing a power supply waveform of each preset region and relative voltage harmonic content of each order harmonic wave of the power supply, obtaining power data of the preset region, and storing the power data; according to the stored power data of the preset region, performing various combinations on the content of each order harmonic wave in the power data and a fundamental wave in the power supply, using a combination which has the greatest impact on preset performance of a to-be-tested air-conditioning electric device as a standard waveform of an actual power supply; using the standard waveform of the actual power supply to test the air-conditioning electric device, to obtain a test result of preset performance of the air-conditioning electric device. The method uses the standard waveform of the actual power supply to test the air-conditioning electric device, so that each item of performance of a product satisfies actual use requirement, and the product is ensured to normally operate under a maximum damaging external condition. A problem that a product which has passed the test has operation faults in different environments.

The invention discloses a mode switching method and device. The method comprises the following steps: receiving a mode switching command, wherein the mode switching command comprises mode switching information; resolving the mode switching information and acquiring an initial mode and a target mode; and performing mode switching according to the initial mode and the target mode, and displaying and / or hiding an icon of an application correlated with the target mode. Through adoption of the mode switching method and device, the problem that applications installed on conventional mobile terminal equipment such as mobile phones in the initial mode, particularly in a conventional mode are not suitable for all users to use is solved, and a mode switching method which is oriented to different users and meets actual use requirements is provided.

The invention discloses a controlled wedge block type bidirectional overrunning clutch. The controlled wedge block type bidirectional overrunning clutch comprises an outer ring, an inner ring, a plurality of anticlockwise wedge blocks located between the outer ring and the inner ring, a plurality of clockwise wedge blocks located between the outer ring and the inner ring, a holder which is located between the outer ring and the inner ring and used for holding the anticlockwise wedge blocks and the clockwise wedge blocks, and a control panel used for controlling the anticlockwise wedge blocks and the clockwise wedge blocks to rotate. Each wedge block in the anticlockwise wedge blocks and the clockwise wedge blocks is provided with a first working face and a second working face. The first working faces of the anticlockwise wedge blocks and the first working faces of the clockwise wedge blocks make contact with the working face of the outer ring permanently, and the second working faces of the anticlockwise wedge blocks and the second working faces of the clockwise wedge blocks can make contact with or leave the working face of the inner ring through rotation of the control panel. The overrunning clutch disclosed by the invention is good in universality and controllable in program.

The invention provides a method and an apparatus for measuring solubility of a refrigerant in refrigerant oil. The apparatus comprises equilibrium still, a refrigerant injection system, a circulatory system, a temperature-control system, a densitometer, and a temperature and pressure measuring system. Compared with the prior art, the method and the apparatus of the invention are easily realized, more important, by measuring the liquid density in the equilibrium still and other general parameters as well as employing relative algorithm which is different with the algorithm in the prior art, solubility of the refrigerant oil is accurately calculated; in addition, the circulatory system is employed for introducing the liquid in the equilibrium still from an outlet of the equilibrium still to an inlet of the equilibrium still, mixing and dissolving of the refrigerant and the refrigerant oil are accelerated, and the gas-liquid phase balance can be reached in a faster mode. The method and the apparatus of the invention are more suitable for the wider scope and pressure scope, which basically and completely satisfy the requirement of practical usage.

The invention discloses a voice scoring method and device, a computer device and a storage medium. The method comprises the following steps of if a matching degree measurement request is received, randomly selecting a text sentence as a target text sentence; generating input prompt information according to the target text sentence in order to prompt a user for voice information corresponding to the target text sentence; if the voice information input by the user according to the input prompt information is received, converting the voice information into first pinyin information through a preset voice conversion model; converting the target text sentence into second pinyin information through a preset text conversion model; calculating the matching degree between the first pinyin information and the second pinyin information according to a preset matching degree calculation model to obtain a voice score of the user. On the basis of a voice processing technology, the voice score of the user is obtained through calculation, that is to say that the matching degree between the voice information input by the user and mandarin can be obtained accurately, and the actual use demand of the user is met.

The invention discloses a hot air type asphalt pavement heating device for thermal regeneration of an old asphalt pavement, which comprises a chassis truck, wherein a hot air generating device is arranged on the chassis truck, and comprises an air heating furnace for heating air to generate hot air, and a bottomless hot air hood is movably arranged below the chassis chuck; a first air outlet holefor conveying the hot air to the ground is formed in the hot air hood, and the air heating furnace supplies the hot air to the first air outlet hole through a hot air conveying pipe; the hot air hoodis peripherally provided with an air shield felt which may be in contact with the ground, and the hot air hood is connected to the air heating furnace through a hot air recovery pipe. The hot air hoodforming a relatively closed space with the pavement is arranged at the bottom of the heating device provided by the invention, and after the hot air generated by the heating device acts on the ground, the hot air can be recovered by the hot air hood, and supplied to the air heating furnace to be reused, thereby effectively improving the utilization efficiency of the hot air and saving energy.

The invention discloses an LMS (least mean square) method for updating a coefficient of a self-adaptive equalizer without frequency difference and phase difference feedback and relates to the technical field of coherent light communication. The LMS method comprises steps as follows: an X polarization receipt signal and a Y polarization receipt signal of the self-adaptive equalizer are subjected to time domain equalization; the error formula of time domain equalization is defined; the coefficient of the self-adaptive equalizer is updated with a gradient algorithm according to the error definition to guarantee that the self-adaptive equalizer constantly tracks changes of the polarization state and frequency difference and phase difference feedback is not required. With the adoption of the LMS method, updating of the coefficient of the self-adaptive equalizer does not depend on frequency difference and phase difference feedback any more, a coherent light communication system can correctly track the changes of the polarization state or even extreme changes of the polarization state, and the robustness of the system is guaranteed.

The invention proposes a high-precision self-resetting probe-type displacement measurement device and a measurement method. The measurement device comprises a bottom part support unit, a linear motion unit, a linear drive unit and a top part connection unit. The linear motion unit and the linear drive unit are mounted between the bottom part support unit and the top part connection unit in parallel and opposite. The bottom part support unit and the top part connection unit are arranged in parallel. The linear drive unit and the linear motion unit are connected to control the probe in the linear motion unit to vertically move upwards and downwards so as to realize the automatic measurement and self-resetting. The linear motion unit further comprises a displacement sensor to measure the displacement amount of the probe in the vertical direction. According the method, the face-to-face working manner of the linear motion unit and the linear drive unit is utilized for the contact type measurement. With the method, high-precision self-resetting automatic measurement function can be realized. The measurement method is simple and convenient, ensures relatively high stability and reliability, shortens the detection time, increases the measurement efficiency and guarantees the measurement accuracy.

The embodiment of the invention provides a method and a system for program change. The method comprises the following steps: a control terminal acquires state data of a program terminal, and performs a risk analysis on the state data, so as to obtain the risk grade of the program terminal; the control terminal adjusts an audit flow for a changed program for the program terminal in real time according to the risk grade, and audits a changed program according to the audit flow; the control terminal issues the audited changed program to the program terminal. The system specifically comprises an acquisition module, a risk module, a flow audit module and an issuing module; the acquisition module is used for acquiring the state data of the program terminal; the risk module is used for performing risk analysis on the state data, so as to obtain the risk grade of the program terminal; the flow audit module is used for adjusting the audit flow of the changed program for the program terminal in real time according to the risk grade, and auditing the changed program according to the audit flow; the issuing module is used for issuing the audited changed program to the program terminal.

The invention relates to a control method of an LED public lighting system, which is characterized in that according to a use condition of the LED public lighting system, when the LED public lighting system has high use efficiency, high power is output, and when the LED public lighting system has low use efficiency, power is reduced step by step for controlling to form an energy conservation power supply timetable in which the use conditions of the LED public light system correspond to stepped power value through that a PWM mode is used for controlling the LED lighting system.