189results about How to "Meet cooling requirements" patented technology

The invention provides a battery thermal management system and an energy storage container. The battery thermal management system comprises a control device, a cooling device and a temperature sensor.The temperature sensor is arranged on the battery module and is used for detecting the temperature of the battery module and sending a temperature signal to the control device. The cooling device comprises a refrigerator and an air channel, wherein the air outlet of the refrigerator is communicated with the air inlet of the air channel, and the air outlet of the air channel is arranged on the battery module; the control device is electrically connected with the temperature sensor and the refrigerator respectively; and the control device controls the working state of the refrigerator accordingto the temperature signal. The control device of the invention judges the temperature of the battery module according to the temperature signal, and then controls the refrigerator to work and generate cooling gas, the cooling gas is released to the battery module through an air duct, the battery module is effectively cooled and radiated, the cooling efficiency is high, the cooling requirements ofthe battery module are met, the battery is guaranteed to work effectively, and the service life of the energy storage container is prevented from being influenced by the relatively high temperature of the battery module.

The invention discloses a method for controlling a cooling system of an electric automobile, which comprises the following steps: detecting the temperature of a motor stator and the temperature of an inverter through an entire automobile controller, comparing the temperatures with the set temperature threshold of the motor rotor for turning on an electronic water pump, the temperature threshold of the inverter for turning on the electronic water pump, the temperature threshold of the motor stator for turning off the electronic water pump, the temperature threshold of the inverter for turning off the electronic water pump, the temperature threshold of the motor rotor for turning on a fan, the temperature threshold of the inverter for turning on the fan, the temperature threshold of the motor rotor for turning off the fan, and the temperature threshold of the inverter for turning off the fan, and controlling the working conditions of the water pump and the fan according to the comparison results. By using the control method, the working conditions of the electronic water pump and the fan can be controlled reasonably, and the system can be ensured to work in a high-efficiency interval, thus the working safety of the system is greatly improved.

The invention discloses a water pump. The water pump comprises a pump body and a blade, wherein a part of the blade is arranged in the pump body, the blade is driven to be capable of moving relative to the pump body so as to enable a distance between one end of the blade located outside the pump body and the center of the pump body to be adjustable. By adjusting the distance between the outer end of the blade and the center of the pump body, centrifugal force provided by the water pump is changed, and further flow adjustment is achieved. For example, when the water pump is used for cooling an engine, the length of the blade extending out of the pump body can be adjusted according to the working condition of the engine, accordingly appropriate coolant flows can be obtained, the engine is fully cooled, engine overcooling or overheating phenomenon of the engine is avoided, and the service life of the engine is prolonged.

The invention relates to a method for controlling a cooling system of a hybrid vehicle, which can reasonably control operating conditions of an electronic water pump and a fan, guarantee that the system is operated within a high-efficiency section, and guarantee the safety of the system. The method for controlling the cooling system of the hybrid vehicle adopts the technical proposal that the electronic water pump, a motor water jacket, a hybrid controller and a radiator form a loop; the electronic water pump makes a liquid coolant flow in the loop; and the fan performs heat dissipation on the liquid coolant which flows through the radiator. The method for controlling the cooling system of the hybrid vehicle is characterized in that a control module of the cooling system controls the on / off of the electronic water pump and the fan according to the temperature of a motor stator and the temperature of an inverter in the hybrid controller.

The invention discloses a chip cooling device which comprises a cooling room positioned at the bottom of the device and matched with the chip, a cooling liquid pond stored with cooling liquid, a firstmicro channel, a first micro pump, a second micro channel, a micro nozzle, a third micro channel, a second micro pump, a fourth micro channel, a condenser and a micropore, wherein one end of the first micro pump is communicated with the cooling liquid pond by the first micro channel and the other end is communicated with the micro nozzle by the second micro channel; the micro nozzle is arranged above the cooling room and communicated with the cooling room; one end of the second micro pump is communicated with the cooling room by the third micro channel and the other end is communicated with the condenser by the fourth micro channel; the condenser is positioned above the cooling liquid pond and a condensing channel is arranged in the interior of the condenser; and a radiating fin is arranged on the top of the condensing channel which is communicated with the cooling liquid pond by the micropore. The chip cooling device has small volume, high heat dissipation efficiency, very high controllability and working flexibility and can meet the cooling requirements of the chip in different working conditions.

The invention provides an application method and an application system of a multifunctional cooling tower. The application system of the multifunctional cooling tower is characterized in that the application system can provide a natural cold source and / or a water cooling mechanical cold source; refrigeration equipment, a three-way valve I, an inner circulation system of a closed cooling tower, a system pressure stabilization and water replenishing device, a circulating pump, a three-way valve II and a water chiller are orderly communicated by pipes and form a first loop; and the water chiller, a three-way valve III, a spray pump and an outer circulation system of the closed cooling tower are orderly communicated by pipes and form a second loop. The application system and the application method of the multifunctional cooling tower can provide natural cold source states and flexibly select cold source taking ways according to temperatures of an inlet and an outlet of the refrigeration equipment and a natural environment, realize that the closed cooling tower has functions of the existing closed cooling tower and the existing open cooling tower, avoid utilization of an open cooling tower, reduce a cost and energy consumption, save energy and a floor space, reduce installation and maintenance time, improve reliability and prolong a service life of the whole application system.

The invention discloses a kind of titanium alloy profile wire. The related tianium alloy profile wire is a board with multilayer titanium alloy hollow structure which involves interlayer with cooling slots. It is made up of the inner scale board with the thickness from 0.3mm to 1.0mm, the outer layer's titanium alloy board with the thickness from 0.3mm to 1.0mm, and the titanium alloy interlayer board with cooling slots between the above mentioned two boards. The molecule infilterating between layers forms a homogeneous matrix with no interface with the thickness from 2.0mm to 10.00mm.The process for manufacturing the board includes following steps: the manufacture of the mould, the preparing and manufacture of the board, installing and molding of the mould with rising temperature, diffusing connection, the first molding, the second molding, cooling and incising process border. It makes use of the technology of combination of SPF and DB, makes application of the technology of the dissolveable screw-demolding core in the investment casting production process. Through twice molding, it accomplishes the processing of the titanium alloy profile wire, makes it the functional material. It provides the aircraft's cabin with the material which has the cooling function under the assurance of the intensity and stiffness. It has a good perspective for its wide application.

The invention discloses an angle-variable fan. An electromagnetic valve is used for controlling oil pressure to achieve control over parallelism and non-parallelism of blade angles. The problem of changing airflow intensity is solved at low cost, and therefore the effect of changing the airflow direction is achieved by means of positive and negative angle adjustment of non-parallel angles, and the purposes of automatically cleaning a water tank and improving the heat dissipation efficiency are achieved. Compared with the prior art, the angle-variable fan is simple in structure, low in cost and capable of meeting requirements of engineering application.

The invention provides a portable electronic device and a heat dissipation control method and a heat dissipation system suitable for the portable electronic device. The heat dissipation system comprises a fan, a fan driving unit and a control unit, wherein after the control unit monitors the state that the portable electronic device executes a program with high energy consumption, a control instruction is sent to the fan driving unit, and the fan is controlled to perform corresponding operation. In this way, the heat dissipation demand of the portable electronic device can be better met.

The invention relates to a cab air conditioner used for adsorbing the tail gas of a truck to cool, comprising generators, a condenser, a liquid receiver, a throttle, an air conditioner of an air cooler containing ammonia, a desorption check valve unit, an adsorption check valve unit, a tail gas input programmable valve unit, a cooling water input programmable valve unit, a PLC programmable controller, a cooling water storage tank, a water pump and a chiller which are communicated by a pipeline valve into a loop; the PLC programmable controller is used for programmable controlling; the tail gas of a truck engine is used for heating and desorbing one of the generators; circulating cooling water is used for cooling and adsorbing the other two generators, thus forming three generator adsorption cooling systems, and further forming desorption and adsorption circulation of ammonia; the cooling circulation of ammonia drives the ammonia cooling fan to cool the truck cab. The air conditioner of the invention combines a multi-generator adsorption cooling system and high-temperature adsorbent, and still effectively realizes adsorption and cooling under the conditions that the cooling water is higher than air temperature, and realizes the air-cooled circulation of cooling water for the generators.

The invention discloses a high total pressure large-flow wheel disk side beveling type back-ward impeller fan, belonging to the technical field of fans. The fan is characterized by being composed of an angle iron flange, a wind scooper, an air intake barrel, a rotor cap, an impeller, the outer barrel of an air outlet barrel, the inner barrel of the air outlet barrel, a guide vane, a motor, a bracket and the like, wherein the inlet of the fan is provided with the wind scooper and extends into the inlet part of the impeller; the hub of the impeller is additionally provided with the rotor cap; the outlet of the impeller, i.e. the edge of the wheel disk, adopts a bevelling structure, and the impeller vane has two types of linear type and circular arc type; the joint assembly point of the air intake barrel and the air outlet barrel of the impeller, i.e. the wheel cover side of the impeller outlet, is provided with the baffle; the isopachous guide vane is welded between the inner barrel of the air outlet barrel and the outer barrel of the air outlet barrel; the side of the inner barrel and outer barrel of the air outlet barrel, which is near the wheel disk of the impeller, is opened; and the air outlet of the fan is divided into a main runner air outlet and a motor cooling flow air outlet. The invention not only satisfies the requirements of high total pressure and large flow operation of the cooling fan but also improves the air flowing situation in the fan to lower flowing loss and noise.

The invention provides a cooling and conveying device, and belongs to the technical field of conveying devices. The cooling and conveying device comprises a tank, a spindle, a driving mechanism, a feed inlet, a discharge outlet and a cooling mechanism. Advancing blades are intermittently arranged on the spindle and comprise cavity matrixes and spiral blades, the spiral blades are arranged on the cavity matrixes, the cooling mechanism comprises a water inlet pipe, communicating pipes and a water outlet pipe, the water inlet pipe, the communicating pipes and the water outlet pipe are arranged in the spindle, and the water inlet pipe, the cavity matrixes and the water outlet pipe are sequentially communicated with one another via the communicating pipes. The cooling and conveying device has the advantages that the cooling and conveying device is novel in structure and reasonable in design and can be applied to mixing, conveying and cooling expanded ammonium nitrate explosive, the expanded ammonium nitrate explosive can be sufficiently mixed, products are good in free-running property and stable in quality, and good cooling effects can be realized.

The invention relates to an interstage cooling system of a water-saving compressor. The interstage cooling system comprises a compressor preceding stage (1), an interstage cooler (2), a compressor backward stage (4), a first cooling pump (5) and a water cooling tower (3), and a cooling coil (2-1) is arranged on the interstage cooler (2). The interstage cooling system of the water-saving compressor is characterized in that an air cooling tower (6) and corresponding second cooling water pump (9) are added to the system; the cooling coil (2-1) is partitioned into a high-temperature zone (A) and a low-temperature zone (B); a cooling water pipeline of the high-temperature zone (A) is connected with the air cooling tower (6); the cooling water pipeline of the low-temperature zone (B) is connected with the water cooling tower; and compressed air discharged from the compressor preceding stage (1) firstly passes through the high-temperature zone (A) of the cooling coil (2-1) and then enters the low-temperature zone (B) after entering the interstage cooler (2). The interstage cooling system of the water-saving compressor has the advantages that water resources can be saved.

The invention discloses a method for molding an iron-based powder laser cladding pipe, and relates to a pipe molding method. The method comprises the following steps: carrying out pipe molding path planning by using KUKA.SimPro2.0 software according to the position and related size of a model pipe; by taking a first point of a circular trace determined by a solver as an initial point, approaching the first circular trace according to the anti-clockwise direction, returning to the original initial point from a terminal point, then lifting a cladding head for 1mm in the Z-axis direction at the position, and repeating the circular trace by still taking the point as the initial point; firstly cladding 10 times in the Z-axis direction according to the method, observing the actual forming effect and then determining subsequent processing schemes; finally forming thin-wall round cooling pipelines with complicated shapes according with the usage requirements; and directly burying the pipelines into a metal cast mold with cooling pipelines with complicated shapes in the internal part, so that the finally manufactured mold can meet the cooling requirements in performance. Thus, the mold can play better efficacy in production.

The invention discloses a water pump and a vehicle provided with the same. The water pump comprises a pump body and a blade, wherein a part of the blade is arranged in the pump body, the blade is driven to be capable of moving relative to the pump body so as to enable a distance between one end of the blade located outside the pump body and the center of the pump body to be adjustable. By adjusting the distance between the outer end of the blade and the center of the pump body, centrifugal force provided by the water pump is changed, and convection volume adjustment is achieved. For example, when the water pump is used for cooling an engine, the length of the blade extending out of the pump body can be adjusted according to the working condition of the engine, accordingly appropriate coolant flows can be obtained, the engine is fully cooled, engine overcooling or overheating phenomenon of the engine is avoided, and the service life of the engine is prolonged.

The invention discloses a refrigerator with a forced refrigerating function and a control method thereof. The refrigerator comprises a box body, door bodies, a trigger switch and a controller, wherein chambers are defined in the box body; the door bodies are arranged on the box body and are used for opening and closing the chambers; the trigger switch is used for switching the refrigerator from a normal working mode to a forced refrigerating mode; and the controller is used for controlling a refrigerating system to carry out forced refrigeration on the chambers after the refrigerator enters the forced refrigerating mode and controlling the refrigerator to enter the normal working mode after reaching preset time. According to the refrigerator with the forced refrigerating function and the control method thereof, which are disclosed by the invention, the requirement of users for cooling each chamber of the refrigerator under special conditions is met; complex components do not need to be additionally arranged; the refrigerator can be implemented by a simple control circuit; and the refrigerator has the advantages of simplicity, convenience and easiness for operation.

The invention provides a water cooling structure of an axial magnetic flux permanent-magnet wind driven generator. The water cooling structure comprises a stator iron core and a stator winding wound on the stator iron core, wherein a cooling sandwich layer is arranged in a disc body of the stator iron core, the surface of the cooling sandwich layer is provided with a water inlet and a water outlet, a cooling flow passage connected with the water inlet and the water outlet is arranged inside the cooling sandwich layer, is in a double-helix structure in the radial direction of a motor and is connected through a bent pipe in a position near to a rotating shaft in the disc body of the stator iron. The water cooling structure has the advantages that the power density of the axial magnetic flux permanent-magnet wind driven generator can be improved to the highest power, in addition, the stator winding temperature of the motor is effectively reduced, and the local overheat point is prevented from generating inside the motor.

The invention discloses a sealed cooling tower and solves the problems that an existing cooling tower is filled with polyvinyl chloride packing and the heat exchange efficiency is low. The sealed tower comprises a tower body, a spraying system, a heat exchange part and a fan, wherein the heat exchange part is a cooler; multiple shell type heat exchange units are vertically arranged in the cooler at intervals; a spraying and air flow channel is formed between the outer walls of two adjacent heat exchange units; at least one inlet and at least one outlet are formed in each heat exchange unit; at least one set of to-be-cooled medium channel penetrating through the inlet and the outlet of each heat exchange unit is formed in the heat exchange unit; the inlets of the heat exchange units are communicated with one another and are converged to form a to-be-cooled liquid medium inlet; the outlets of the heat exchange units are communicated with one another and are converged to form a to-be-cooled liquid medium outlet. The inside structure of the sealed cooling tower is simplified and the cooling efficiency is improved.

The invention provides a proton accelerator cooling water temperature control system and method. A secondary cooling water circulation system ensures that the temperature of output secondary cooling water meets the technological requirement through the PID control of cooling tower fans and the control of a second electromagnetic three-way valve of frozen water, and primary circulating water cooledby a load and secondary cooling water exchange heat through a primary plate exchanger to reduce the temperature. In addition, a primary cooling water control system makes the cooling water meet the cooling requirement of proton acceleration equipment through common adjustment of the serial PID control of a first electromagnetic three-way valve of secondary cooling water and the PID control of electric heaters.

The invention belongs to the field of superconducting circular accelerators, and provides a cooling method for a superconducting magnet of a superconducting circular accelerator in order to solve the problems that in China, the existing cooling methods for superconducting magnets are complex in procedure and large in time consumption for cooling and the like. The cooling method includes the steps of (1) vacuumizing the superconducting magnet; (2) conducting liquid nitrogen refrigeration on the superconducting magnet, and meanwhile adjusting length of a pulling rod of the superconducting magnet in a radial direction; (3) exhausting liquid nitrogen and vacuumizing the superconducting magnet; (4) conducting liquid helium refrigeration on the superconducting magnet to complete cooling. The cooling method for the superconducting magnet of the superconducting circular accelerator adopts a two-segment cooling mode including a liquid nitrogen cooling process and a liquid helium cooling process; the cooling procedures are designed reasonably, the cooling time is short, the operation is convenient, and the cooling method can effectively reduce consumption amount of the liquid nitrogen and the liquid helium on the premise of meeting the cooling demands for superconducting coils.

The invention provides a radiating system of a vehicle matching hydraulic retarder, which comprises an engine and a cooling loop system connected with an engine cooling channel; a hydraulic retarder is arranged on the cooling loop system; a water outlet pipe of the hydraulic retarder is linked with an assistant cooling pipeline in parallel, and a control module for controlling its conduction is arranged on the assistant cooling pipeline when the water effluent temperature of the hydraulic retarder exceeds a preset value. The assistant cooling pipeline is linked to the water outlet pipe of thehydraulic retarder in parallel, and water temperature is monitored by the control module; when the monitored effluent temperature exceeds the preset value, the assistant cooling pipeline is conducted,thus the assistant cooling pipeline is connected to the cooling loop system to cool together, the cooling ability of the vehicle radiating system is improved, and the cooling requirement of the vehicle cooling system is satisfied. The invention further provides a vehicle.

The invention relates to a method and apparatus to regulate oil pressure via controllable piston cooling jets. A method of regulating oil pressure within an engine assembly is provided. The engine assembly includes an oil pump configured to provide oil to an oil system of the engine assembly; a piston cooling jet configured to direct a jet of oil from the oil system towards a piston of an engine;and an electronic control valve configured to control the flow of oil to the piston cooling jet. The method includes operating the electronic control valve to provide a flow rate of oil above a threshold flow rate to the piston cooling jet when the engine assembly is operating above a threshold power output or engine running speed; and regulating the pressure of oil within the oil system when theengine assembly is operating below the threshold power output or engine running speed, by operating the electronic control valve.

The invention relates to a single water evaporation air conditioner. The air conditioner comprises an upper cover, a fan, a water distribution pipe, a humidifying screen, an inlet air filter screen, a base, a water tank, a water pump, water supply and return pipes and an electric control device, wherein the water distribution pipe and the humidifying screen are in a ring-shaped structure, the water distribution is arranged on the humidifying screen, the fan is arranged at the center of the base, namely in the ring formed by the water distribution pipe and the humidifying screen, the humidifying screen is arranged in a ring-shaped groove of the base, the base is surrounded by the inlet air filter screen, the water supply and return pipes are arranged among the water distribution pipe, the base and the water tank, and the electric control device is connected with the fan and the water pump. The air conditioner has the following advantages: the structure is compact; a periodic water supply and return mode to guide return water; and the base is integrated with a concentration cavity, a water collecting tank structure and related pipes, thus cost is reduced. The single water evaporation air conditioner can be widely applied to the roofs of various vehicles and watchhouses.

The invention discloses a testing apparatus of an engine valve mechanism rack, and the testing apparatus comprises a rack, a water supply system, an oil supply system and a power mechanism, wherein the water supply system comprises a water supply plate and a water return plate respectively connected with the bottom of a cylinder cover and its side, a water supply cavity is formed inside the water supply plate which is provided with a plurality of water supply outlets connected with water inlets on the cylinder cover bottom, a water return cavity is formed inside the water return plate which is provided with water return outlets connected with the water return cavity, the water supply inlet is connected with the water return outlet through a pipe on which a circulating pump and a water tank are arranged, the oil supply system comprises an oil pipe connected with oil inlets and oil outlets on the cylinder cover, an oil pump and an oil tank. Through the testing apparatus of the engine valve mechanism rack, the water supply system and the oil supply system are simplified when multiple cylinders and valve mechanisms are realized in simulation, thus the testing apparatus is conveniently installed and disassembled, thereby effectively preventing water and oil from leakage.

The invention discloses a mining TBM (tunnel boring machine) water circulation system and a mining TBM water circulation method. The system comprises an external water source, an internal circulation water supply pipe, an internal circulation waterway, an internal circulation water outlet pipe and various mining TBM external devices. The external water source is connected with an inlet of the internal circulation water supply pipe, an outlet of the internal circulation water supply pipe is connected with an inlet of the internal circulation waterway, an outlet of the internal circulation waterway is connected with the internal circulation water outlet pipe, and an outlet of the internal circulation water outlet pipe is connected to a water inlet of each mining TBM external device. The external water source supplies water to an internal circulation tank and then distributes to each water pump; each water pump supplies water to the corresponding mining TBM internal device, and water is recycled after use and discharged to water supply pipes of the external devices to be used by the mining TBM external devices; water used by the mining TBM external devices is directly discharged to a roadway floor. Cooling effects of the water circulation system are greatly improved, water consumption and cooling requirements of the devices can be met, the operating rate of the devices is increased, and TMB quick efficient tunneling is guaranteed powerfully.

The invention provides a double-beam input laser cooling atom three-dimensional magneto-optical trap device, and aims to overcome the defects that an optical path system of an existing magneto-opticaltrap is easily affected by the external environment, and generated cold atoms have large-amplitude random jitter, and extra errors are introduced although random jittering of cold atom parameters caused by optical fiber factors is reduced. A unique three-dimensional MOT optical path transmission topology is designed, six polarization maintaining optical fibers required originally are reduced to two polarization maintaining optical fibers, and the influence of unstable incident laser polarization degree and light intensity fluctuation on the generated cold atom quality is greatly eliminated; polarization characteristics of laser beams are utilized, multiple times of light beam splitting and reflection are performed, independent adjustment of power and polarization of six beams of laser used for atom cooling is achieved under the condition that only two paths of input light exist, particularly, the power of the six beams of light which are oppositely emitted in pairs at a convergence point can be adjusted to be strictly equal, and the influence caused by inconsistent fluctuation pace of the power of the six beams of light in the working process of the device is greatly reduced.

The invention discloses an intelligent temperature-control mattress. The intelligent temperature-control mattress comprises a mattress body and a main engine, wherein the mattress body is provided with a ventilation layer, a lining layer, a temperature control layer, a filling layer and an anti-slip layer in sequence from top to bottom; a water circulation pipe is laid in the temperature control layer; the temperature control layer is provided with a sleep monitor and a first temperature sensor; the main engine comprises a water tank assembly, a control panel, a heat dissipation opening, a water feeding opening and a liquid crystal display screen arranged on the control panel; the water tank assembly comprises a water tank, a semiconductor cooler, a fan, a water feeding opening of a watertank, a second temperature sensor, a water pump, a self-operated electric control temperature adjusting valve and a stirring part. The intelligent temperature-control mattress disclosed by the invention has the advantages that the semiconductor cooler can meet the requirements of heating and cooling the mattress at the same time, and is simple in structure and good in safety.

The invention discloses a cooling and purifying system for spent fuel of a small reactor. Water is taken from a suppression pool by a cooling and purifying loop and sent into a safety injection watertank, the spent fuel is stored in the safety injection water tank, water in the safety injection water tank is cooled by the cooling and purifying loop, waste heat of the spent fuel is taken out, andmeanwhile, cooled water in the safety injection water tank is purified by the cooling and purifying loop; the spent fuel stored in the safety injection water tank is moved out, and water in the safetyinjection water tank is extracted into the suppression pool by the cooling and purifying loop. With application of the cooling and purifying system for the spent fuel of the small reactor, the problem about water source supplement caused by the fact that the spent fuel is stored by the safety injection water tank can be solved, a sufficient water source is provided for spent fuel cooling, and thecooling requirement of the spent fuel during refuelling of the small reactor is met; water purification function of the safety injection water tank for storing the spent fuel temporarily during refuelling of the small reactor is realized; the system is reasonable in structural design, safe, reliable and easy to repair and maintain.

The invention discloses a preparation method of a solid-liquid two-phase metal-polymer heat-conducting phase-change composite material, and belongs to the technical field of polymer composites. The solid-liquid two-phase coexisting metal and a polymer material are mixed to prepare the heat-conducting phase-change composite material. According to the method, the high thermal conductivity of the composite material is realized by compounding metal in a solid-liquid coexistence region in a metal phase diagram with a polymer matrix and utilizing the high thermal conductivity coefficient and phase change latent heat of the metal; according to the composite material, binary, ternary and multivariate phase diagrams of metal are utilized, and the solid-liquid phase ratio and phase change latent heat of the metal are regulated and controlled through metal composition and a metal phase diagram lever law, so that the heat conductivity coefficient of the prepared heat-conducting phase change composite material ranges from 0.2 W m <-1 > K <-1 > to 30.0 W m <-1 > K <-1 >, and the heat dissipation requirements of various electronic devices are met.