1691 results about "Outdoor temperature" patented technology

The invention discloses a control method of an air conditioner. The control method comprises the following steps: S1, detecting current indoor temperature, current outdoor temperature and current indoor relative humidity; S2, acquiring indoor temperature grade corresponding to the current indoor temperature and acquiring relation grade between the current indoor temperature and the current outdoor temperature; S3, determining a current operation mode of the air conditioner according to the indoor temperature grade and the current indoor relative humidity and relation grade. According to the method provided by the embodiment of the invention, operation of setting temperature by a user is not required for the air conditioner in the entire operation process of the air conditioner, so automatic switching in a refrigeration mode, a heating mode, an air supply mode, a dehumidification mode and the like of the air conditioner is realized, the operation steps of the user are simplified, the comfort is improved, and the user experience is improved. The invention also discloses a control device of the air conditioner and the air conditioner with the control device.

The invention provides an air conditioner as well as a control method and device thereof, wherein the method comprises the following steps: acquiring an indoor temperature/humidity, an outdoor temperature/humidity and user parameters; calculating an initial heat load or initial cold load according to the indoor temperature/humidity, the outdoor temperature/humidity and the user parameters; calculating the output capacity of the air conditioner according to the initial heat load or initial cold load and a preset cooling rate or heating rate; and determining the frequency of a compressor according to the output capacity of the air conditioner. Through the invention, the air conditioner can run with a frequency generated when the running efficiency of the air conditioner is the optimum efficiency, thereby reducing the power consumption.

Illustrative embodiments of the present invention are directed to a method and system for disaggregating climate control energy use from non-climate control energy use for a building. The method includes receiving a series of building energy use values and corresponding outdoor temperature values for a time period. Each of the energy use values and outdoor temperature values is associated with a time interval. The method further includes determining a series of temperature difference values for the time period based on a difference in temperature between a predetermined baseline temperature and each of the outdoor temperature values. A regression analysis is used to determine a climate control coefficient and a non-climate control coefficient from the energy use values and temperature difference values. The climate control coefficient and/or the non-climate control coefficient is used to determine climate control energy use and/or non-climate control energy use for the building.

Real-time monitoring of an energy characteristic of a building such as an energy performance of the building or a carbon offset of the building is performed by first computing a heat transfer coefficient of the building from nighttime steady-state thermal load data of the building and from nighttime steady-state indoor and outdoor temperature data of the building. A thermal inertia of the building is then computed from nighttime transient indoor temperature data of the building and nighttime transient thermal load data of the building. During daytime, a solar radiation gain coefficient is computed from daytime thermal load data, daytime indoor and outdoor temperature data, incident solar radiation data, and the heat transfer coefficient. The energy characteristic of the building is then estimated in real time from the heat transfer coefficient, the thermal inertia, and the solar radiation gain coefficient.

The invention discloses a cold source centralized digital control method based on energy consumption monitoring. The cold source centralized digital control method based on energy consumption monitoring comprises the following steps that a, real-time monitoring is conducted on power utilization, water utilization, the cooling quantity, the temperature, the pressure and the equipment state of a cold source system of a central air conditioner; b, energy consumption data and system state data collected in the step a are summarized, real-time refrigerating efficiency of the cold source system is calculated according to operating power parameters of a water chilling unit, a chilled water pump, a cooling water pump and a cooling tower fan in the system and the refrigerating capacity of the water chilling unit, forecast energy consumption data at present are obtained through forecasting according to outdoor temperature and humidity parameters at present, indoor temperature and humidity parameters at present and a load forecast model, the forecast energy consumption data and the energy consumption data which are actually monitored are compared, problems existing in the use process of a refrigerating system are found, and an optimized operation control strategy of the cold source system is formed; c, the optimized operation control strategy formed in the step b is conducted, and optimized operation control is achieved through a direct digital controller and an electrically operated valve connected with the direct digital controller.

A building controller is configured to designate one or more stored parameters as local or global. Parameters that are designated as global may be selectively communicated to remote devices and, parameters that are designated as local, may remain local to the building controller. In some instances, the remote devices may be selectable by a user, include all the other devices on the network, and/or include devices that share a common wireless accessory (e.g. an outdoor temperature sensor).

The invention discloses a thermostat dehumidification control method of an air conditioner. The air conditioner comprises a compressor, a condenser, an electronic expansion valve, an evaporator, a four-way reversing valve, an outdoor fan, an indoor fan, an indoor temperature sensor, an indoor humidity sensor and an outdoor temperature sensor; and the evaporator is divided into a heating section and a dehumidifying section by a dehumidifying electromagnetic valve. The dehumidifying operating mode of the air conditioner is divided into a cold room dehumidification control mode and a thermostat dehumidification control mode according to the difference between the temperature detected by the indoor temperature sensor and the temperature set by a remote controller. When the air conditioner is in the thermostat dehumidification control mode, the thermostat dehumidification control mode is further subdivided into three control areas according to the relative humidity detected by the indoor temperature sensor, thus the purposes of reducing the indoor temperature and keeping the temperature constant are achieved by controlling the frequency of the compressor, the rotation speed of the outdoor fan and various valves, and a conformable indoor environment is provided for the user.

The invention relates to an energy-saving optimized control system and an energy-saving optimized control method for a refrigerator room. The energy-saving optimized control system comprises an industrial control computer, a flow sensor, a temperature sensor, an outdoor temperature and humidity sensor, a three-phase active power transmitter, a water pump frequency converter and a cooling tower fan frequency converter which are connected with a programmable logic controller respectively, wherein the programmable logic controller communicates with the industrial control computer through an industrial Ethernet; and an RS485 communication interface module is connected with a water cooling unit and communicates with the industrial control computer through a ModBus protocol. A mathematical model of relationships between the energy consumption and running parameters of each equipment in the refrigerator room is established to regulate the running state of each equipment in combination with real-time refrigeration loads and weather parameters, thereby fulfilling the aim of making the lowest running energy consumption of the whole refrigerator room at the premise of meeting the refrigeration loads.

The invention discloses an air conditioner for automatically adjusting the air quality and an adjusting method thereof. The air conditioner comprises an indoor air quality sensor, an outdoor air quality sensor, an indoor humidity sensor, an outdoor humidity sensor, an indoor dust sensor, an outdoor dust sensor, an indoor temperature sensor, an outdoor temperature sensor and a ventilating device, wherein the ventilating device is at least provided with a PG motor. In addition, the air conditioner also comprises an air quality control module, a humidity control module, a temperature control module and a ventilating control module, wherein the air quality control module is used for comparing indoor air quality data with outdoor air quality data and for generating and outputting a ventilating signal or a non-ventilating signal; the humidity control module is used for comparing indoor humidity data with outdoor humidity data and for generating and outputting a ventilating signal or a non-ventilating signal; the temperature control module is used for comparing indoor temperature data with outdoor temperature data and for generating and outputting a ventilating signal or a non-ventilating signal; and the ventilating control module is used for starting the PG motor to ventilate under the conditions of simultaneously meeting all the ventilating signals and for turning the PG motor off under the condition of meeting part of the ventilating signals. The invention automatically dehumidifies, humidifies and controls the ventilating amount and has a scientific air quality improving method.

The invention relates to an air-conditioner, in particular to a method for automatically detecting the lack of refrigerant in the air-conditioner. The invention discloses a method for automatically detecting the lack of refrigerant in the air-conditioner in order to solve the problems that the prior art can not automatically detect the fault of the lack of refrigerant or give an alarm to result in high maintenance cost and low maintenance efficiency. The automatic detecting method comprises the following steps of: detecting the difference between the indoor temperature and the temperature of an inner coiled tube, the difference between the outdoor temperature and the temperature of an outer coiled tube and the running current value of a compressor at real time after the air-conditioner runs; and compared with the normal conditions, judging whether the large deviation exists or not so as to judge whether the present refrigerant lacks or not. The invention has the advantages of automatically detecting the fault of the lack of refrigerant in the air-conditioner, immediately giving an alarm, reminding users of the associated maintenance, reducing the maintenance cost and improving the efficiency; and the invention is suitable for detecting whether the air-conditioner lacks of refrigerant or not.

The invention discloses a control circuit of an air-conditioner outdoor draught fan. The control circuit comprises an outdoor temperature measurement detecting unit, a condenser pipe temperature detecting unit, a main control unit and a draught fan drive unit. The outdoor temperature measurement detecting unit is used for detecting outdoor environment temperature values when the air-conditioner outdoor draught fan is operated; the condenser pipe temperature detecting unit is used for detecting outdoor condenser coil pipe temperature values when the air-conditioner outdoor draught fan is operated, the main control unit is used for confirming a adjustment range of the rotating speed of the outdoor draught fan according to the outdoor environment temperature values, confirming the initial gear values in the adjustment range of the outdoor draught fan, comparing the outdoor condenser coil pipe temperature values with preset reference temperature, confirming rotating speed adjustment gear values in the adjustment range of the outdoor draught fan, and outputting corresponding rotating speed commands to the draught fan drive unit according to the initial gear values or adjustment gear values; and the draught fan drive unit drives the outdoor draught fan load according to the control commands to adjust the outdoor draught fan to operate in a corresponding speed. The invention further provides an air-conditioner containing the control circuit and a control method of the air-conditioner outdoor draught fan. The control circuit of the air-conditioner outdoor draught fan is low in cost and more stable in system.

The invention discloses a self-cleaning control method for air conditioners. The self-cleaning control method includes enabling the air conditioners to detect outdoor environmental temperatures, detecting the temperatures of inlets and outlets of outdoor heat exchangers or detecting the cumulative run time of compressors; enabling the air conditioners to carry out heating running to allow frost to condense on the outdoor heat exchangers when the outdoor environmental temperatures are lower than or equal to preset outdoor temperatures and temperature difference between the inlets and the outlets of the outdoor heat exchangers is lower than or equal to preset temperature difference or the cumulative run time of the compressors is longer than or equal to preset run time; switching the air conditioners into a refrigerating mode. The self-cleaning control method for the air conditioners has the advantages that the air conditioners carry out heating running to allow the frost to condense on the outdoor heat exchangers and then are switched into the refrigerating mode to defrost the outdoor heat exchangers, accordingly, dust accumulated on the outdoor heat exchangers can be cleaned by condensed water generated after the outdoor heat exchangers are defrosted and can be effectively reduced, heat exchange effects of the air conditioners can be effectively improved, and energy consumption can be reduced.

The invention provides a control method and device for improving heating speed of an air conditioner. The method comprises the following steps of: collecting the temperature of an indoor coil pipe when the air conditioner is at a standby state and an outdoor air temperature is less than or equal to a first outdoor temperature and an indoor temperature is less than or equal to the first indoor temperature; preheating the indoor coil pipe when the indoor coil pipe temperature is less than the first set temperature: starting up a compressor for preheating the indoor coil pipe, and stopping the compressor until the indoor coil pipe temperature is greater than or equal to a first set temperature, and delaying to stop an outdoor fan; and preheating the indoor coil pipe repeatedly when the indoor coil pipe temperature is less than a second set temperature. The control device comprises a starting module, a determination module and a preheating module, wherein the determination module is used for comparing the indoor coil pipe temperature and the preset temperature; and the preheating module controls the starting and stopping of the compressor according to the determined result so as to preheat the indoor coil pipe repeatedly. According to the invention, the heating speed of the air conditioner can be improved, and the effect that heating can be carried out once the air conditioner is started up is realized.

The invention discloses a dynamic climate compensation method for centralized heating. Firstly, the outdoor temperature is predicted, water supply and return temperatures are adjusted some time ahead according to the predicted value of the outdoor temperature, and the hysteresis of pipe network adjustment in the manner that adjustment is performed while sampling is overcome. The outdoor temperature of the next day is predicted according to local historical meteorological data and weather forecast of the meteorological department, and the value is used as basic data for prediction of a thermal load; and then the thermal load is predicted, that is, the thermal load curve of the next day is calculated according to the outdoor temperature. With the method, the outdoor temperature is reasonably predicted so as to realize advanced dynamic adjustment of a climate compensator; heating medium parameters of a heating system are adjusted by the aid of an adjusting model according to the thermal load value set in advance, a heat source is changed from original wide passive heating into active heating, on the premise that the indoor temperature for the user is stable, the operation adjusting indictor of the heating system within the specified time are given in advance, the heating efficiency is improved, and the heating energy consumption is reduced.

A heat pump system including a water-cooled type heat exchanger, which is a heat supply means, mounted on a first bypass line bypassing a second indoor heat exchanger to collect waste heat of vehicle electric devices to thereby enhance a heating efficiency of the heat pump system. The heat pump system for a vehicle includes: a branch line for connecting a refrigerant circulation line of the second indoor heat exchanger and the first bypass line with each other; a second bypass line, which bypasses an outdoor heat exchanger; and a control part that controls a flow of the indoor air to be introduced into an air-conditioning case, whereby the heat pump system can minimize influences of the outdoor air of low temperature even when the outdoor temperature is below zero, enhance the operation and the heating performance of the heat pump system by collecting waste heat of the vehicle electric devices and heat sources of the indoor air, and increase the mileage of the vehicle by minimizing operation of an electric heater.

The sufficiency of refrigerant charge in an air conditioning system is determined by a comparison of two sensed temperatures in the system, one being the liquid line temperature and the other being either the outdoor temperature or the condenser coil temperature. In one embodiment the two sensed temperatures are displayed on respective thermochromic strips which are so calibrated and juxtaposed as to provide a visual indication, by the relative positions of the two displayed sensed temperatures, as to whether the refrigerant charge is adequate. In another embodiment, the sensed liquid line temperature is displayed by way of a plurality of LEDs and the other temperature is displayed by way of a marker on a temperature scale. If the two displayed temperatures are aligned, then the refrigerant charge is optimized, and if they are not aligned, the system is undercharged or overcharged.

The invention discloses a device which can automatically control temperature and humidity, as well as the method thereof. The device of the invention comprises an air conditioner, a damping machine, a dehumidifying machine, a ventilation system, a constant temperature lamp, a constant humidity lamp, a display and a printer, as well as a central control system which is connected with the air conditioner, the damping machine, the dehumidifying machine, the ventilation system, the constant temperature lamp, the constant humidity lamp, the display and the printer. The method of the invention comprises the following steps: the indoor temperature and the indoor humidity which need to be controlled are determined and the maximum and the minimum of the temperature and the maximum and the minimum of the humidity are set according to the needs, and the indoor and the outdoor temperature and the indoor and the outdoor humidity are measured; whether the ventilation system, the air conditioner, the damping machine and the dehumidifying starts or set under the constant temperature or constant humidity state is judged according to the indoor temperature and the indoor humidity which need to be controlled as well as the difference between the maximum and the minimum of the temperature and the maximum and the minimum of the humidity which are set and the indoor and the outdoor temperature and the indoor and the outdoor humidity; the ventilation system, the air conditioner, the damping machine and the dehumidifying are started or set under the constant temperature or constant humidity state according to the judgment of the result.

The invention discloses an aggregation air conditioning load scheduling method based on temperature set value adjustment. The method comprises the following steps: (1) acquiring the temperature set value and outdoor temperature prediction value of each air conditioner aggregation group through a bilateral information channel; (2) adjusting and estimating the load increase/decrease scheme of each air conditioner aggregation group based on the temperature set values; (3) acquiring a load increase/decrease target issued by a superior scheduling department; (4) establishing an aggregation air conditioner scheduling decision model, and solving; (5) issuing an air conditioner control command through the bilateral information channel. By adopting the aggregation air conditioning load scheduling method, load increase/decrease service can be provided for electric power system scheduling on the premise of not influencing the user comfort by using air conditioning equipment of a user, so that the user turns from an electric energy user to a participant of an electric power system and participates in running of the electric power system; meanwhile, by using the method, technical guidance can be provided for the innovation of the scheduling mode of a power grid scheduling department.

The invention belongs to the field of air conditioner control, and particularly relates to an energy-saving control method of an air conditioner. By using the control method of the air conditioner provided by the invention, outdoor environment temperature and indoor temperature are detected in real time, the magnitude between the outdoor real-time temperature and a preset outdoor temperature threshold is judged, under a refrigeration mode and the condition that the outdoor real-time temperature is smaller than the outdoor temperature threshold, or under a heating mode and the condition that the outdoor real-time temperature is larger than the outdoor temperature threshold, the air conditioner is controlled to operate according to the mode that a target temperature T1 is the sum of the indoor real-time temperature and the preset temperature difference; otherwise the air condition operates according to the originally set temperature. By using the control method, the operation parameters of the air conditioner can be automatically adjusted anytime, a user is prevented from operating the air condition frequently, the temperature is controlled in the optimum comfortable state, the refrigeration and heating requirements of the user can be met, electricity can be saved, and environment is protected.

The invention provides a control method of an air conditioner, the air conditioner and a storage medium. When a starting instruction is received, the indoor space is monitored, and when a human body is detected, a human body image in a monitoring area is obtained; next, a clothes ROI is obtained based on the human body image, and when a training model matched with the clothes ROI exists in a pre-arranged clothes classifier, the warm-keeping index of clothes currently worn by the human body is obtained; then, the cold-thermal sensation level of the human body is judged according to the warm-keeping index and/or the current outdoor temperature; and finally, whether a current operating mode of the air conditioner is matched with the cold-thermal sensation level or not is judged, and an alarmprompt or an adjusting instruction is output when the current operating mode of the air conditioner is not matched with the cold-thermal sensation level. The situation that the operation mode of the air conditioner is mistaken due to misoperation of the human body, and consequently a user has heatstroke or catch a cold is avoided, the comfort of the air conditioner is improved, and the health of the user is ensured.

The invention belongs to the field of air conditioner control, and particularly relates to an energy-saving control method of an air conditioner. By using the control method of the air conditioner provided by the invention, according to the requirement of a user, outdoor real-time temperature Tw and indoor real-time temperature Tn are detected, the temperature difference delta Ts between the indoor real-time temperature Tn and the indoor target temperature Tm is calculated; according to a comparison result of the outdoor real-time temperature Tw and a preset outdoor temperature threshold Ty, the air conditioner is controlled to operate under a first preset frequency or a second preset frequency corresponding to the temperature difference delta Ts. The operation frequency of the air conditioner is adjusted anytime, the operation temperature of the air conditioner is controlled in the optimum comfortable state, the refrigeration and heating requirements of the user can be met, the user experience is improved, the power consumption of the air conditioner is reduced, and energy-saving and environment-protecting effects are realized.

Provided are methods and apparatus that determine a benchmark of energy consumption for an energy system and utilize the determined benchmark in a variety of ways. Once determined, the determined benchmark may be compared to current energy consumption and current outdoor temperature to verify proper operation of the system and identify deviations in system operation. The benchmark may be used to determine the impact of an implemented change in the operation of the system. The determined benchmark may also be used to contract for a term in an agreement and to verify the satisfaction of a term in an agreement.

The invention provides a sheath rubber for wind electric power generation cable, belonging to the rubber technical field, comprising chloroprene rubber (CR), cis-butadiene rubber (BR) with high elasticity, good anti-wear property and anti low temperature property and other raw material. The sheath rubber will not obviously lose flexibility, elasticity and generate crack even though the outdoor temperature in cold area is -50 DEG C. The sheath rubber has features of torsion resistance, high rebound elasticity, strong torsional flexibility resistance and even twist fracture resistance.

The invention relates to a regulating method of a center heating system in an urban area. The method includes the steps: (1) fitting an outdoor temperature with a regression curve of a heating index, and correcting the regression curve according to practical heating situations, (2) by predicting and calculating heat load needed by a whole heat-supply network, providing guidance for a heat source, (3) calculating and setting a secondary water supply/return temperature according to a primary water supply/return temperature of heat supply output, heat-supply network averaging control is carried out on heat exchange stations according to different distances between the heat exchange stations and the heat source, and avoiding the phenomenon that users at the near end are warm and users at the far end are cold, and (4) regulating the secondary water supply/return temperature in real time by controlling the regulating range of a valve. Therefore, heat supply quality is improved, energy consumption is saved, heat energy waste is reduced, the whole system can achieve the aim of supplying heat according to needs, and the fact that the heat supply effect of users is uniform is guaranteed.

The invention discloses a central air-conditioning modeling and controlling strategy on the basis of demand response, which comprises the following steps of building a room model, namely the relation between the indoor temperature and outdoor temperature of the room and sensible heat cooling load; building a center air-conditioning model suitable for the system operation of the demand response, namely the relation between air conditioning load and a decision variable; determining a controlling strategy, namely making an objective function, a control variable, a constraint condition and the like clear; solving the objective function by adopting a harmony search algorithm combining with a state space truncation method; obtaining a result, and performing analysis and treatment on the result. According to the central air-conditioning modeling and controlling strategy on the basis of the demand response, through meticulously building the models, making the strategy of multiple control variables cooperative optimization clear, scientific theoretical support is provided for the central air-conditioning to participate in the system operation of the demand response.

The invention discloses a control method and a device of heating system, wherein the control method comprises the following steps: obtaining a predicted outdoor temperature; calculating a heat leakage coefficient; calculating a target heat load based on the heat leakage coefficient, the predicted outdoor temperature and a user designated indoor temperature; using the target heat load to calculate a target water supply flux and a target water supply temperature; and controlling the heating system to supply heat to the user based on the target water supply flux and the target water supply temperature. By using the control method and device of heating system, the problems that the adjustment is delayed and the energy resource is wasted because the floor heated room in the prior art uses the same water supply temperature and flux in supplying heat; therefore, the effect of adjusting the water supply flux and the water supply temperature of the heating system based on the real-time outdoor temperature is achieved.

The invention provides an air conditioner temperature control method and an air conditioner temperature control system, wherein the method includes the following steps: indoor environment temperature and outdoor environment temperature are detected; which one of a plurality of preset temperature ranges the outdoor environment temperature lies is judged, and the temperature relation between target temperature and the outdoor environment temperature corresponding to the preset temperature range is obtained; according to the temperature relation, the target temperature is calculated; the relation between the target temperature and the indoor environment temperature is judged, and according to a judgment result, the operating state of a compressor is controlled; the target temperature increases as the outdoor environment temperature increases. The regulable range of indoor environment temperature is wider, corresponding temperature control curves are adopted for the different preset temperature ranges, the change of outdoor environment temperature can be more accurately reflected by an indoor environment, the difference between indoor temperature and outdoor temperature is small, users can be more easily adapted to the change of the difference between indoor temperature and outdoor temperature, the occurrence of air-conditioning diseases such as dizziness, sunstroke and cold can be prevented, and comfort is good.

The invention provides an air conditioner control method and an air conditioner. The method comprises the following steps: when receiving an operation mode command of a one-key control key, collecting an outdoor environment temperature detected by an outdoor temperature sensor; judging the sizes of the outdoor environment temperature, a first pre-set temperature and a second pre-set temperature; if the outdoor environment temperature is more than or equal to the first pre-set temperature, controlling the air conditioner to carry out a refrigeration operation mode; if the outdoor environment temperature is less than or equal to the second pre-set temperature, controlling the air conditioner to carry out a heating operation mode; and if the outdoor environment temperature is more than the second pre-set temperature and smaller than the first pre-set temperature, controlling the air conditioner to carry out mode judgment according to an air conditioner standby state, the outdoor environment temperature, an indoor environment temperature and a remote control set temperature. A remote controller or the indoor unit is provided with the one-key control key so that the air conditioner can automatically select the operation mode when a consumer presses the key; the air conditioner is simple and convenient to operate, so that the consumer can enjoy the convenience of one-key control and the comfort of products is improved.

The invention discloses a base station air conditioner energy saving monitoring system, comprising master control machine, air conditioner controller, outdoor temperature and humidity sensors, indoor temperature and humidity sensors, and outdoor and indoor temperature and humidity sensors respectively collect outdoor and indoor temperature and humidity signals and transmit them to the master control machine; the master control machine compare outdoor and indoor temperature and humidity signals and calculates reasonable air-conditioner operating parameters, where when the indoor temperature and humidity are higher than the outdoor temperature and humidity, the master control machine switches off the air conditioner and switches on ventilating unit to make outdoor and indoor heat exchange. And it can in time adjust operating parameters of air conditioners, effectively reducing indoor temperature to save energy and prolong mechanical service life of air conditioners.

The invention relates to a temperature control system with indoor and outdoor temperature difference consideration, which is used for assisting an air conditioning device for air conditioning control. The temperature control system comprises an outdoor device and an indoor device, wherein the outdoor device and the indoor device are communicated; the outdoor device is provided with an outdoor temperature detecting unit; the indoor device is provided with a processing unit, and the processing unit is used for generating and transmitting target temperature to the air conditioning device so as to facilitate the air conditioning device to carry out the air conditioning control; and the target temperature is one of preset temperature and indoor set temperature, which is closer to the outdoor temperature, wherein the preset temperature is generated through calculation according to the outdoor temperature and a preset temperature difference value. The invention also relates to a temperature control device, the air conditioning device and a temperature control method with the indoor and outdoor temperature difference consideration.