252results about How to "Small rate of change" patented technology

A process and associated apparatus used to prepare a thermoplastic composite from a plurality of plies of thermoplastic resin prepregs. The prepregs are formed into a composite structure under two chambers; a rigid outer chamber (of any convenient size or shape) and a second flexible inner chamber containing a prepreg lay-up. The absolute pressures are reduced concurrently in a stepwise method in both chambers. This concurrent, stepped pressure reduction is accomplished at a rate which prevents the vacuum bag from moving far from the prepregs, and prevents wrinkles from forming in the prepregs. Pinching off the diffusion paths required for the removal of unwanted gases is eliminated. The lay-up is then heated and the absolute pressure in the outer rigid chamber is increased. This pressure constrains the flexible inner chamber during out-gassing of the thermoplastic resin, preventing wrinkles from forming in the prepregs. The absolute pressure in the outer rigid chamber is increased to atmospheric pressure or greater causing the prepregs to consolidate. A low absolute pressure is maintained in the flexible inner chamber. The temperature is then increased to the cure temperature of the resin and held for a time sufficient for the resin to cure. The resulting consolidated thermoplastic resin is substantially void free and detectable wrinkles are absent.

The invention relates to a low thermal expansion coefficient NaMxAlySiz high entropy alloy and a preparation method thereof, the chemical components of the alloy are as follows: 75 <= a <= 100%, 0 <= x <= 10%, 0<= y<= 10%, 0<= z<= 5%, N is arbitrary three or more than three of Ta, Nb, Hf, Zr, Ti, Mo and W, and M is any one or more than one of V, Mn, Fe, Co, Ni and Cr. The alloy phase structure is as follows: a body centered cubic solid solution and an intermetallic compound. The alloy is prepared by arc melting method in three stages. The NaMxAlySiz high entropy alloy has a low thermal expansion coefficient at the temperature in the range of room temperature to 1000 DEG C, the change rate is less than 20%, and the alloy has a broad application prospect in the high temperature industrial field.

A braking apparatus for a vehicle includes a hydraulic brake apparatus generating a basic hydraulic pressure so that a basic hydraulic braking force is generated at wheels, the hydraulic brake apparatus generating a controlled hydraulic pressure so that a controlled hydraulic braking force is generated at the wheels, a regenerative brake apparatus causing a regenerative braking force to be generated at any of the wheels, and braking force replacement controlling means for gradually replacing the regenerative braking force with the controlled hydraulic braking force while braking during which at least the regenerative braking force is applied for a purpose of achieving a braking force replacement control to ensure a total braking force required for the wheels by decreasing the regenerativebraking force at a gradient within a predetermined range and by increasing the controlled hydraulic braking force in response to the decrease of the regenerative braking force.

The invention relates to a preparation method of a microporous kyanite-based lightweight insulating refractory material. The preparation method is realized by comprising the following steps: (1) by taking kyanite, auxiliary materials and a cementing material as raw materials, adding a certain amount of dispersing agent, thickening time control agent and foam stabilizer, premixing, adding a certain amount of water, and mixing to prepare uniform slurry; (2) adding a certain amount of foaming agent in the slurry, mechanically agitating and foaming to prepare uniform foam slurry; (3) injecting the foam slurry into a mould, standing under a room-temperature environment so as to be cued and formed; (4) demoulding a green body, and then drying and sintering to obtain the microporous kyanite-based lightweight insulating refractory material. The prepared microporous kyanite-based lightweight insulating refractory material has the advantages of microfine air bore aperture (20-200mum), low volume density, high porosity, high strength, small sintering line change rate, low thermal conductivity, high usage temperature and the like. The raw materials are mainly kyanite, and other raw materials are common materials in refractory material industry, and are non-toxic and low-cost. The preparation method is simple and is easily controlled for the technology, and is suitable for industrial production.

A drive control system for an electric vehicle and a method of drive control of the electric vehicle. The drive control system for the electric vehicle includes a drive motor target torque calculation processing device for calculating a drive motor target torque representing a target torque of a drive motor; and a drive motor target torque restriction processing device that judges whether or not a parking mechanism is in operation and, if the parking mechanism is in operation, restricts variations in the drive motor target torque.

The invention belongs to the technical field of wind power generation, and discloses a comprehensive control system adopting a doubly-fed wind generator participated in power grid primary frequency modulation. The control system comprises a rotor rotary speed control module, a simulation inertia control module, a droop control module, a rotary speed protection and power determination module and apitch angle control module. After the wind generator is participated in frequency modulation, the power grid inertia is equivalently enlarged, so that the doubly-fed asynchronous wind generator can have inertia response on the power grid frequent as the conventional synchronous generator, thereby lowering change rate of the power grid frequency; and by controlling the rotary speed and the pitch angle, the wind generator output is lowered, so that the wind generator has certain active backup capacity to be participated in primary frequency modulation, thereby lowering steady-state error of thefrequency.

A semiconductor device and an electro-optical device that ensures a stable output are provided even when there is a change in a source-drain current in a saturated operation region of a thin film transistor due to kink effects. The thin film transistor has a multi-gate structure with a polycrystalline silicon film as an active layer, and a source-side first thin film transistor portion and a drain-side second thin film transistor portion connected in series. The first thin film transistor portion has a drain-side back gate electrode that is connected with a first front gate electrode. The second thin film transistor portion has a source-side back gate electrode that is connected with a second front gate electrode.

The invention relates to an energy storage battery system power giving method for stabilizing wind power grid connection power fluctuation. The method comprises the following steps of: (1) determining a sampling control period, and initializing a filtering time constant and a wind power grid connection target power offset value; (2) reading current battery charge percent; (3) calculating a smoothened wind power grid connection power target value; and (4) calculating the output target value of an energy storage battery system. According to the method provided by the invention, the change rate of wind power output power fluctuation can be reduced, power smoothening standby of the energy storage battery system is considered simultaneously, and the wind power smoothening capability of an energy storage battery is brought into full play.

A bicycle comprising a front triangle and a rear wheel having a rear wheel axis, a rear wheel suspension system further comprising a link further comprising a first pivotal axis for connection to said front triangle and a second pivotal axis for connection to a rear wheel swingarm, wherein the distance from said second pivotal axis to a first vertical plane decreases during a first portion of suspension compression and increases during a second portion of suspension compression; and wherein said first vertical plane is defined as a plane which is perpendicular to the ground and offset in the direction of the rear wheel with respect to the first and second pivotal axis. During the first portion of suspension compression and during the second portion of suspension compression the front triangle remains stationary with respect to the first vertical plane.

The invention discloses a full bridge topology power supply, a control method and communication equipment. An inductance clamping circuit capable of self-adjusting resonance is arranged in a full bridge topology power supply device, inductance value features can be automatically adjusted with the utilization self-adjusted resonance inductance in the inductance clamping circuit and according to the size of passed current, a control circuit controls each switch tube of a full bridge topology, wide zero voltage switch load range, small circulation energy and small duty ratio loss are achieved, and therefore light loading vice side rectifying loss is reduced, light loading converting efficiency is enhanced, performance of flexible switches of a full bridge is improved, wide load range zero voltage opening up of primary side switch tubes of the full bridge is favorable for being achieved, switch loss is reduced, and efficiency of full load range is improved. Besides, the changing rate of primary side current is lowered by the self-adjusted resonance inductance, the vice side rectifier tube voltage spike is clamped through the self-adjusting resonance inductance clamping circuit, and therefore vice side rectifier tube source drain electrode voltage spike is lowered, and application reliability is improved.

The invention discloses a method for smoothing output power of a wind power station by utilizing an energy storage system. In the method, not only wind power is introduced to predict or rectify the output power of the wind power station, but an improved self-adaptive filtering algorithm is applied. Since the output power of the wind power station is rectified by predicting the wind power, the change rate of the output power of the wind power station is decreased, and the output power of the wind power station can meet standards to inject into a power grid. By employing the self-adaptive filtering algorithm, regarding to the input power in different time, time weight coefficient in an adaptive filtering structure can be automatically calculated according to the input, so that the defect that different input cannot correspond to different filtering time constant by utilizing a low pass filter smoothing method in the past can be overcome. After the smoothing method is employed to smooth the output power of the wind power station, the output voltage of the wind power station is kept stable, fluctuation and flicker of the power grid voltage is reduced, harmonic pollution is reduced and accidents are reduced.

An organic light emitting diode (OLED) display includes a substrate; a scan line formed on the substrate and applying a scan signal; a data line and a driving voltage line intersecting the scan line and respectively applying a data signal and a driving voltage; a switching TFT connected to the scan line and data line; a driving TFT connected to a switching drain electrode of the switching TFT and the driving voltage line; an OLED connected to the driving drain electrode of the driving TFT; a storage capacitor connected between the driving voltage line and the driving gate electrode of the driving TFT; and a boosting capacitor including a first boosting capacitor plate connected to the driving gate electrode and a second boosting capacitor plate overlapping the first boosting capacitor plate and connected to the scan line, where an area of the first boosting capacitor plate of the boosting capacitor is larger than an area of the second boosting capacitor plate.

A rudder control device for a boat can include a handle position sensor for detecting an operation angle of a handle. An engine control unit can be provided for receiving a detection signal from the handle position sensor. A motor can be provided for receiving a control signal from the engine control unit to drive a steering member to a predetermined rotation angle corresponding to the operation angle. The engine control unit can receive a signal from a speed sensor for detecting a boat speed to control an upper limit of the rotation angle to be smaller when the boat speed is higher than a predetermined value than when not.

The invention discloses a high-speed phase splitting circuit with a band spreading function, belongs to the field of communication circuits, and aims to solve the problem of limitation of the bandwidth of a trans-impedance amplifier in the conventional phase splitting circuit on the working frequency of a pre-amplifier. The high-speed phase splitting circuit with the band spreading function comprises a first P-channel metal oxide semiconductor (PMOS) transistor M1, a resistor R1, a resistor R2, a phase splitting amplifier and an integrator, wherein the phase splitting amplifier is formed by cascading a first amplifier A1 and a second amplifier A2; the integrator consists of a third amplifier A3, a resistor R3, a resistor R4 and a capacitor C1; a source of the first PMOS transistor M1 is connected with a power supply through the resistor R1 and also connected with a non-inverting input end of the first amplifier A1, and a drain of the first PMOS transistor M1 is grounded through the resistor R2; two output ends of the second amplifier A2 are respectively connected with two input ends of the integrator; and the output end of the integrator is connected with an inverting input end of the first amplifier A1.

The invention discloses insulated oil-resistant sealing rubber. The insulated oil-resistant sealing rubber is prepared from the following raw materials in parts by mass: 40-80 parts of nitrile rubber, 20-60 parts of chloroprene rubber, 1-1.5 parts of an accelerant, 0.5-2 parts of sulfur, 0.8-3.2 parts of magnesium oxide, 4-5 parts of zinc oxide, 45-55 parts of carbon black, 2-4 parts of an anti-ageing agent, 2-3 parts of stearic acid and 10-15 parts of a plasticizer. The invention further discloses a preparation method for the rubber. The rubber has good processing performance, ageing resistance and oil resistance.

The invention relates to an anti-ultraviolet bidirectional stretching polyester film and a preparation method thereof. The an anti-ultraviolet bidirectional stretching polyester film is composed of anupper surface layer, a core layer, and a lower surface layer. The core layer is composed of an anti-ultraviolet absorbent and polyethylene glycol terephthalate slice; the upper surface layer is composed of the anti-ultraviolet absorbent, an anti-adhesion agent, and the polyethylene glycol terephthalate slice; and the lower surface layer is composed of the anti-adhesion agent and the modified polyethylene glycol terephthalate slice. The product has the characteristics of UV resistance, heat sealing, high intensity, hydrolysis resistance, corrosion resistance, and high thermostability, can be widely used in the fields of outdoor product package and building, and belongs to the functional film, performance is outstanding, cost is low, and the method has a wide application prospect.

The invention relates to a clay light-weight brick and a preparation method thereof. The technical scheme is as follows: the preparation method comprises the following steps of: firstly applying 30-40wt% of kyanite or flint clay, 35-45wt% of coal ash and 15-35wt% of plastic clays as raw materials, additionally adding 35-55wt% of pore-forming agents of the raw materials or 2-4wt% of polystyrene spheres, then additionally adding 6-10wt% of bonding agents of the raw materials, uniformly mixing, granulating, drying, and baking at 120-300 DEG C to prepare clay light-weight aggregates; then applying 10-20wt% of first-stage aggregates, 20-30wt% of second-stage aggregates, 15-25wt% of three-stage aggregates, 15-25wt% of the coal ash, 10-20wt% of the kyanite or the flint clay and 10-20wt% of the plastic clays as mixed materials, additionally adding 40-60wt% of the pore-forming agents of the mixed materials or 2-4wt% of the polystyrene spheres, then additionally adding 5-15wt% of the bonding agents of the mixed materials, uniformly mixing, forming, drying, and keeping temperature at 1200-1400 DEG C for 3-10 hours. The preparation method disclosed by the invention has the advantages of low cost, energy conservation and environmental friendliness; the product prepared through the method disclosed by the invention has the advantages of low volume density, good compressive strength as well as small linear changing rate and low heat conduction coefficient after being burnt.