391 results about "Controlled ventilation" patented technology

The invention relates to the technical field of granary ventilation and energy consumption optimization, in particular to an intelligent granary ventilation and energy consumption optimization decision-making method based on reinforcement learning, and the method comprises the steps: obtaining the internal and external multi-dimensional state data of a granary, respectively constructing a basic state vector, a space correlation feature vector and a grain condition change trend vector based on the multi-dimensional state data inside and outside the granary; combining the basic state vector, the space correlation feature vector and the grain condition change trend vector into a space-time feature tensor, inputting the space-time feature tensor into a space-time topology perception decision model based on a graph attention network, and outputting an optimal composite action vector for controlling ventilation equipment; and analyzing and converting the optimal composite action vector to drive ventilation equipment of the granary to execute control. According to the method, through fusion of space-time topology perception and deep reinforcement learning, accurate prediction and active regulation and control of the granary state are realized, and energy consumption of a ventilation system can be reduced to the greatest extent while grain storage safety is ensured.

The invention relates to the technical field of mine mining, and discloses an underground multi-parameter environment monitoring method, which comprises the following steps of: acquiring equipment pose, vibration spectrum and environment parameters in real time through a multi-source sensor, performing space-time alignment, filtering noise reduction and feature extraction on original data, outputting a standardized state vector, and performing data processing on the standardized state vector; fusing the pose data, the vibration signals and the environmental parameters under a unified space-time reference to construct a multi-dimensional feature matrix; and carrying out dimension reduction and redundant information elimination by adopting principal component analysis, and outputting a fused equipment state vector. According to the method, through real-time fusion of the equipment pose and the airflow dynamic state, the ventilation equipment is cooperatively regulated and controlled, the interference of mechanical vibration on the gas monitoring precision is eliminated and the reliability of gas concentration detection is guaranteed based on coupling modeling of vibration spectrum and pose drift and intelligent compensation of sensor reading errors, and through space correlation analysis and dynamic air volume optimization, the gas concentration detection accuracy is improved. Wind speed sudden drop caused by tramcar passing is actively eliminated, and roadway global continuous monitoring is achieved.

The invention discloses a new energy vehicle underground garage fire treatment method and system based on the Internet of Things. The system comprises a sensor data acquisition module, an edge calculation and risk assessment module, an early warning and emergency response module and a data storage and cloud platform module. The sensors are arranged at positions such as parking spaces and ventilation systems in a garage, monitor environmental parameters such as temperature, smoke and gas in real time, and transmit data to the edge computing device through the wireless gateway. And the edge calculation module evaluates the fire risk in combination with a fuzzy Bayesian network. And the early warning and emergency response module triggers different levels of alarm signals according to the risk levels, and controls ventilation equipment, fire-fighting equipment and the like in a linkage manner. The data storage module is used for storing monitoring data. The system has the advantages of real-time monitoring, intelligent evaluation, multistage early warning and quick response, is suitable for fire prevention and safety management of closed environments such as underground garages, and effectively improves the accuracy of fire risk prediction and the efficiency of emergency response.

The invention provides a mobile henhouse ventilation regulation and control method and system based on an environment model, and relates to the technical field of intelligent breeding, and the method comprises the steps: obtaining original temperature data, original humidity data, a three-dimensional space wind speed component, an opening geometric distribution data set, and original latitude and longitude coordinate data and time data; calculating a dynamic environment weight coefficient matrix according to the original latitude and longitude coordinate sequence and the time data; generating a self-adaptive heat exchange flow field according to the dynamic environment weight coefficient matrix, the original temperature data and the original humidity data; according to the self-adaptive heat exchange flow field and the trepanning geometric distribution data set, a ventilation compensation amount demand curve is obtained through calculation; generating a ventilation intensity adjusting instruction set according to the ventilation compensation amount demand curve; and according to the ventilation intensity adjusting instruction set, outputting an optimal ventilation control parameter. According to the method, ventilation response self-adaptive accurate matching, airflow dead zone self-suppression and energy consumption-effect dynamic balance under the moving sudden change working condition are achieved.

The invention is suitable for the technical field of automobile intelligent control, and provides an air conditioner seat collaborative cooling control method based on a neural network, which comprises the following steps of: constructing a human body-environment comfortable temperature original index model by collecting a large amount of human body and environment temperature distribution data in advance; on the basis, data acquisition and model comparison are carried out on the real-time human body temperature, the environment temperature and the temperature in a passenger compartment before the passenger gets on the bus, so that the heat comfort in the bus is pre-adjusted most reasonably before the passenger gets on the bus, and a method for cooperatively controlling ventilation and heating of an air conditioner and a seat is utilized; the two are combined to improve the thermal comfort of the passenger and the passenger compartment. And meanwhile, real-time sensing data is quickly processed when a passenger feels uncomfortable in temperature during riding and adjustment is carried out, the body temperature of the passenger and the ambient temperature of a passenger compartment are recorded and are input into a model for correction, so that the body comfort requirement of the passenger is met in a more personalized manner, and the comfort of the passenger in the vehicle running process is improved.

The invention belongs to the technical field of highway tunnel ventilation control, and provides a highway tunnel ventilation control method and system. The method comprises the following steps of multi-source heterogeneous data acquisition, multi-source data fusion, state estimation, traffic flow prediction, dynamic pollution index calculation and multi-target weight generation, rolling optimization with constraints, control execution, model updating and feedback correction. The state sensing precision is improved through multi-source data fusion, real-time accurate estimation and error reduction of a pollutant concentration field and a traffic flow state are realized through a heterogeneous sensor and a Rayleigh fusion technology, the problem of sensing deviation caused by single data in a traditional method is solved, future traffic flow is predicted based on a graph neural network, and the traffic flow sensing accuracy is improved. The fan power is optimized through model prediction control, the ventilation intensity is adjusted in advance, pollutants are prevented from exceeding the standard, the response speed is increased compared with threshold value control, and energy consumption is reduced.

The invention relates to an intelligent ventilation system in a tunnel and a control method thereof, and belongs to the technical field of tunnel ventilation. The intelligent ventilation system in the tunnel comprises a data acquisition unit, a ventilation unit, a control unit, a data storage unit and a data analysis unit, wherein the data acquisition units are mounted in detection sections in a tunnel, and each data acquisition unit comprises a COVI detector, a wind speed and direction detector and a traffic flow detection module; when the CO concentration and the VI exceed threshold values, the ventilation unit is controlled to enter a corresponding working mode; the data analysis unit is used for generating an early warning model according to the data of the data storage unit, and the early warning model is used for obtaining CO concentration and VI data in the future # imgabs0 # time according to the wind speed and wind direction data, the traffic flow, the vehicle type, the fuel oil type data, the CO concentration and the VI change. According to the ventilation system, intervention can be conducted before the pollution concentration is increased, the period of insufficient ventilation is effectively avoided, and it is guaranteed that good air quality is always kept in the tunnel.

The invention provides a method and system for controlling ventilation cooling type permafrost subgrade based on energy dynamic balance, wherein the method comprises the steps of constructing a heat absorption predicting model; and inputting an operating condition combination of a permafrost subgrade into the heat absorption predicting model to produce a predicted heat absorption for the permafrost subgrade, and controlling a cooling system to operate based on the predicted heat absorption. The heat absorption predicting model is constructed based on a seed point algorithm of formula matrix, which comprises the steps of producing a known fitting formula; establishing a formula matrix; and calculating a predictive fitting formula corresponding to a new seed point by known seed points in the formula matrix and an index formula, and then calculating the predicted heat absorption based on the predictive fitting formula.

The invention relates to a multi-mode-based laboratory environment monitoring method and system, and relates to the field of environment monitoring, and the method comprises the steps: obtaining environment information of each animal cabin in a laboratory in a preset historical time period and a monitoring video of each animal cabin, the environment information comprises a temperature change curve, a humidity change curve and an oxygen content change curve, determining an activeness change curve of each animal cabin according to the monitoring video, determining an environment quality change curve of each animal cabin according to the environment information, determining a target cabin of which the activeness reaches a preset activeness threshold according to the activeness change curve, and determining a target cabin of which the activeness reaches a preset activeness threshold according to the target cabin. And judging whether an abnormal cabin exists in the target cabin or not according to the environment quality change curve and the activity change curve, and if yes, controlling a ventilation device to ventilate the abnormal cabin. The method has the effects that the abnormal cabin can be conveniently found in time, and the environment of the abnormal cabin is improved.

Hybrid buildings, hybrid building systems, methods of constructing hybrid buildings, and a method of ventilating such a building are disclosed. First and second building sections forming part of such buildings are also disclosed. One such hybrid residential building (1800) comprises a first building section (1810) and a second building section (1820). The first building section is an on-site construction at a final location for the building and defines an internal volume (1813) that provides a living space (1815) within the building. The second building section defines an internal volume (1823) and is transportable to the final location in a substantially assembled form. The first and second building sections are connected at the final location to form the building. The building comprises a ventilation system (1860) which is configured to supply external air into the building, and to withdraw internal air from the building and to discharge it to the building exterior, to thereby control ventilation of the building.

This invention relates to the field of mining technology and discloses a method for multi-parameter environmental monitoring underground. The method includes the following steps: real-time acquisition of equipment pose, vibration spectrum, and environmental parameters through multi-source sensors; spatiotemporal alignment, filtering and noise reduction, and feature extraction of the raw data; outputting a standardized state vector; fusing pose data, vibration signals, and environmental parameters under a unified spatiotemporal reference to construct a multi-dimensional feature matrix; and using principal component analysis to reduce dimensionality and remove redundant information, outputting the fused equipment state vector. This invention achieves real-time fusion of equipment pose and airflow dynamics, collaboratively controlling ventilation equipment. Based on coupled modeling of vibration spectrum and pose drift, it intelligently compensates for sensor reading errors, eliminates the interference of mechanical vibration on gas monitoring accuracy, and ensures the reliability of gas concentration detection. Through spatial correlation analysis and dynamic airflow optimization, it proactively eliminates sudden drops in wind speed caused by mine car passage, achieving continuous monitoring throughout the roadway.

The disclosure provides a method of operating a (HVAC) system. The method includes measuring a concentration of a gas in the target space, and determining that the concentration exceeds a gas concentration threshold. The method includes determining that operation of the HVAC system in a ventilation mode is indicated to reduce the concentration of the gas. The method includes determining a total capacity of the HVAC system, and determining a current capacity of the HVAC system. The method includes causing the HVAC system to operate in the ventilation mode after validating that the total capacity is greater than the current capacity during operation of the HVAC system in the ventilation mode.

The invention relates to the technical field of tunnel monitoring, and particularly discloses a tunnel monitoring method based on machine vision, which comprises the following steps: S1, dividing sub-periods, acquiring a monitoring image at the starting point of the sub-periods, identifying a target vehicle in the monitoring image, and determining a minimum enclosing rectangle in the monitoring image; calculating a vehicle type score based on the minimum enclosing rectangle, calculating an exhaust emission index, determining a total emission amount in the sub-time period, and if the total emission amount is smaller than a total emission amount threshold value, obtaining a new total emission amount in the next sub-time period; if the total discharge amount is greater than or equal to the total discharge amount threshold value, taking the starting point of the corresponding sub-time period as an adjustment time point; s3, calculating a theoretical distance, determining a target position, and determining a target line; and when the sub-tunnel belongs to any tunnel part, adding 1 to the selection number of the sub-tunnel, determining the total selection number of the single sub-tunnel, and controlling the ventilation system based on the total selection number. The energy consumption of the ventilation system in the tunnel can be reduced.

The invention belongs to the technical field of building ventilation, and particularly discloses an intelligent building ventilation energy-saving system based on AI dynamic adjustment, and the system is characterized in that the system comprises a sensing layer which is used for collecting indoor and outdoor environment parameters in real time; the data transmission layer transmits various data acquired by the sensing layer to a central control system in real time through an Internet of Things communication technology, and is provided with a data caching mechanism; the central control system comprises a data processing module and is used for preprocessing the received data; the AI analysis module is used for establishing an indoor air quality prediction model, a personnel activity mode prediction model and a ventilation system energy consumption model by applying a machine learning algorithm; the control decision module generates an optimal ventilation control strategy; and the execution layer comprises a fresh air fan and an exhaust fan which adopt a frequency conversion technology, and an air supply outlet and an exhaust outlet which are provided with electric air valves, and further comprises a function of receiving a control instruction of the central control system and controlling ventilation equipment in real time.

The utility model provides a building ventilation dustproof pipeline convenient to ventilate, which belongs to the technical field of ventilation dustproof pipelines and comprises a pipeline. The first dustproof pipe is fixedly connected to the side end of the pipeline; the second dustproof pipe is in threaded connection with the side end of the first dustproof pipe through a bolt, and the side end of the second dustproof pipe is fixedly connected with a connecting pipe; the frame is fixedly connected to the side end of the connecting pipe, the fan blades are fixedly connected to the side end of the frame, an adjustable baffle and a valve are installed, a user can accurately control the ventilation quantity and the airflow direction according to actual requirements, unnecessary airflow loss is avoided, and therefore energy is saved. Due to improvement of the sealing performance, interference to indoor and outdoor environments is reduced, energy loss caused by airflow leakage is reduced, and the energy utilization efficiency of the system is further improved.

A method for operating a temperature control system for a structure is disclosed. The method includes monitoring historical data, and controlling the temperature control system to inject outdoor air into the supply duct of the temperature control system based upon historical data. Some embodiments of the system include monitoring an interior and exterior temperature of a structure, defining a first time range and a second time range, associating one or more operating parameters of the temperature control system with the first time range and the second time range, monitoring operational time and operational load of the cooling system for the first time range, and controlling a ventilation subsystem during the second time range based upon the monitored operational time and operational load of the cooling subsystem for the first time range, and the one or more operating parameters of the cooling subsystem associated with the second time range.

The invention relates to the technical field of ventilation control, in particular to a ventilation control method and system for an intelligent ventilation cabinet, a medium and a product, and the method comprises the steps: obtaining a monitoring environment parameter of a to-be-controlled ventilation cabinet in a current monitoring time period, and carrying out the control of the ventilation cabinet based on the monitoring environment parameter and a preset strategy mapping relation; determining an initial ventilation strategy of the to-be-controlled ventilation cabinet in the current monitoring time period; based on the monitored environment parameters, determining historical maintenance time periods corresponding to the monitored environment parameters from historical ventilation records; determining an observation time period, an observation adjustment parameter and an observation adjustment value corresponding to the observation adjustment parameter based on the historical maintenance time period and the monitoring environment parameter, and generating a target ventilation strategy based on the observation time period, the observation adjustment parameter, the observation adjustment value corresponding to the observation adjustment parameter and the initial ventilation strategy; and performing ventilation control on the to-be-controlled ventilation cabinet in the current monitoring time period and the observation time period based on the target ventilation strategy. The timeliness and accuracy in the ventilation control process can be improved conveniently.

The utility model discloses a composite cabin ventilation system meeting dynamic positioning redundancy requirements, which comprises an exhaust shutter, an air inlet shutter and a fan which are positioned in an upper cabin, a structural air duct positioned in a middle cabin and a diesel generator set positioned in a lower cabin, and the air inlet shutter, the fan, the structural air duct and a cavity of the lower cabin are sequentially communicated. The cavity of the lower-layer cabin is communicated to an exhaust shutter through a chimney; and an air brake for controlling the ventilation quantity is arranged between the fan and the structural air duct. According to the utility model, a water cooling mode is utilized to completely replace the heat dissipation air volume of a main part during the design of a conventional cabin ventilation system, and the discharge capacity of a ventilation fan and the size of an air duct are reduced. The internal circulation cooling jet fan does not need to be started, normal operation of the ship can be guaranteed through the frequency conversion fans with the small number and power, and energy conservation and emission reduction are achieved. All the frequency conversion fans and the internal circulation cooling jet fans can work at the same time, the use requirements of tropical areas under extremely hot working conditions are met, and the working condition adaptability of ships is improved.

The invention provides an underground coal mine ventilation control method and device, electronic equipment and a storage medium, and belongs to the technical field of mine ventilation. The method comprises the steps that the type and concentration characteristics of harmful gas in a target area are determined according to data collected by a biosensor array; determining time sequence data of the harmful gas according to the concentration of the harmful gas, and determining a target concentration change rate of the harmful gas according to the time sequence data; according to the concentration of the harmful gas, the target concentration change rate and the current underground acoustic wave characteristics of the coal mine, the target air volume of the target area is determined; according to the target air volume of the target area, the ventilation resistance of the target area and the current opening degree of the ventilation valve, the opening degree of the ventilation valve is controlled, and the ventilation air volume is determined. According to the coal mine underground ventilation control method and device, the electronic equipment and the storage medium, the ventilation quantity can be accurately and timely adjusted.

The invention relates to the field of operating room ventilation, in particular to a ventilation and purification control system based on an intelligent operating room, and aims to solve the problem that a ventilation system running at constant power cannot cope with a complex and changeable dust and bacterium environment, so that the ventilation and purification efficiency is inappropriate. Comprising an air volume management and control unit, a purification rate management and control unit, a ventilation task management unit, a ventilation environment acquisition unit, a purification environment supervision unit and a purification equipment supervision unit. According to the invention, intelligent analysis is carried out according to the dust environment in the operating room and the idle time of the operating room, so that the purification work of the operating room does not influence the normal use of the operating room, the microbial environment in the operating room is monitored, and the operation of the sterilization equipment is intelligently controlled according to the microbial monitoring result; quantitative analysis is carried out according to the dust environment and the microbial environment, air volume control is achieved, the air volume can meet the rapid ventilation requirement of the dust environment, and the ventilation speed can be controlled to guarantee the sterilization effect.

The utility model relates to the technical field of building ventilation equipment, and discloses a fresh air fan air port structure which comprises a shell frame, the upper end of the shell frame is connected with a connecting sleeve through a screw, a gasket is arranged at the contact end of the connecting sleeve and the shell frame, and bolts are distributed on the circumference of the lower wall in the shell frame. According to the utility model, the installation is simple and convenient, the arrangement of the connecting sleeve with a convex structure and the design of a protruding connecting port are adopted, so that the butt joint with a pipeline is convenient, and the installation efficiency is improved; the gasket is arranged between the connecting sleeve and the shell frame, so that the sealing performance is improved, and air leakage and vibration are reduced; the surface cover is magnetically adsorbed with the shell frame through a magnet, so that the surface cover is convenient to disassemble and clean; the size of a gap between the surface cover and the shell frame can be adjusted by adjusting the screwing-in depth of the bolt, the ventilation quantity can be controlled, and the good ventilation effect is achieved.

The invention discloses an energy-saving type ventilation curtain wall and a construction method thereof. The ventilation curtain wall comprises a frame, a mounting piece, an inner-layer curtain wall body, an outer-layer curtain wall body, a shutter, a first meshing piece, a second meshing piece, a driven wheel, a driven piece, a multi-class sensor, a flow guide piece, a ventilation opening, an adjusting piece, a linear driving assembly and a purification assembly. A main control chip is arranged on the outer side of the inner-layer curtain wall; a flow guide piece on the inner side of a frame guides airflow; a ventilation opening and an adjusting piece are matched to control the ventilation quantity; a purification assembly purifies air; the construction method comprises the steps of S1, preparation before construction, S2, base layer treatment, S3, installation of the frame and the inner-layer curtain wall, S4, installation of the outer-layer curtain wall and the flow guide part, S5, installation of the power mechanism, S6, installation of the sensor and the purification assembly and S7, system debugging. Excessive exchange of indoor and outdoor heat can be reduced, energy consumption is reduced, the system adapts to different climates, construction is easy and convenient, and efficiency is high.

The invention relates to the technical field of pressure vessel valves, in particular to a sealing valve device for hydrogen storage. Comprising a pneumatic main body used for power, a ventilation device used for controlling hydrogen circulation, a sealing device used for sealing the air inlet end of the ventilation device in the replacement process and a movable main body arranged in the pneumatic main body and used for controlling ventilation and sealing of the ventilation device, and the rear portion of the ventilation device is fixedly connected with the pneumatic main body. According to the pneumatic device, through the arrangement of the push rod, the positioning block, the rubber ring, the positioning ring, the supporting ring, the rubber conical block, the conical plate, the elastic piece and the sleeve, the rubber conical block can be directly dragged towards one side, the aged rubber conical block is directly taken down and replaced, during installation, the rubber ring is directly arranged on the outer side of the sleeve in a sleeving mode, and the rubber conical block can be conveniently taken down and replaced. The rubber ring and the sleeve are installed on the outer side of the positioning block together, at the moment, the reed is clamped on the outer side of the positioning block, and installation of the rubber conical block is achieved.

The utility model belongs to the technical field of drying equipment, and particularly relates to a ventilation structure of a multifunctional dryer. An upper air pipe is arranged at the top of an inner cavity of the shell, a lower air pipe is arranged at the bottom of the inner cavity of the shell, an air outlet of the fan is connected with the upper air pipe and the lower air pipe through a three-way pipe, the three-way pipe comprises an upper air pipe, a lower air pipe and an air inlet pipe, the upper air pipe is connected with the upper air pipe, the lower air pipe is connected with the lower air pipe, and the air inlet pipe is connected with the air outlet of the fan. The upper air pipe and the lower air pipe are provided with gate assemblies for controlling ventilation of the upper air pipe and the upper air pipe and ventilation of the lower air pipe and the lower air pipe respectively, and the side walls of the upper air pipe and the lower air pipe are provided with a plurality of ventilation openings for ventilation towards an inner cavity of the shell in the length direction of the upper air pipe and the lower air pipe. The drying device can guide hot air flow and is good in drying effect.

The invention provides a control method for linkage equipment matched with a generator set, the linkage equipment comprises generator sets, signal modules, a cooling circulating water system and a ventilation system, and each generator set is in signal connection with the cooling circulating water system and the ventilation system through the signal modules; the cooling circulating water system comprises a cooling water pump control box and a plurality of groups of cooling water pumps, and each generator set outputs a group of starting or stopping signals to the cooling water pump control box through a signal module; after the generator set is started, the cooling water pump control box determines the corresponding number of water pumps which are put into operation according to the group number of starting signals output by the generator set; after the generator set is shut down, the cooling water pump control box determines that the corresponding number of water pumps are shut down according to the group number of the shut-down signals output by the generator set; the generator set outputs starting or stopping signals to the ventilation system through the signal module, and the ventilation system is controlled to start ventilation or stop ventilation. The overall operation efficiency of the generator set is improved.

The waterproof law enforcement recorder comprises a recorder body, a back face clamping mechanism, a hot air blowing mechanism, an adjusting ventilation mechanism and a ventilation auxiliary mechanism, and the adjusting ventilation mechanism comprises a flowing pipe, a pushing frame, a pushing rod, a sealing head, a convex-concave block and a convex-concave groove. The ventilation auxiliary mechanism comprises an adjusting pipe, a threaded block, an inner pushing pipe, a compression frame and a reset spring, the hot air blowing mechanism comprises a top platform, a hot air box, an air blowing fan and an air blowing pipe, dry hot air is provided through heating and air blowing, the situation that the interior of the recorder is damaged due to the humid environment is avoided, internal electronic elements are protected, and the service life of the recorder is prolonged. The performance of the recorder in a low-temperature environment is improved, the ventilation quantity can be accurately controlled through cooperation of a circulating pipe, a sealing head, a convex-concave block and a convex-concave groove, hot air generated by a hot air blowing mechanism is exhausted, the internal circulating efficiency is improved, and the recorder adapts to different environmental conditions.

The invention relates to novel ventilation and air exchange equipment which comprises a ventilation and air exchange module used for achieving circulation and exchange of indoor and outdoor air and energy recovery. The natural energy recovery module is used for collecting natural energy in the natural environment and converting the natural energy into electric energy; the energy management module is connected with the natural energy recovery module and an external power grid, is used for coordinating distribution of renewable energy and power supply of the power grid to supply energy to equipment, and is provided with an energy storage unit for storing redundant electric energy generated by the natural energy recovery module; the AI dynamic air volume adjusting module is used for predicting the predicted air demand reference quantity in the future 30 minutes by analyzing historical environment data and real-time personnel distribution, and calibrating the predicted air demand reference quantity regularly in the execution process; and the intelligent control module is in communication connection with the user intelligent wearable device, collects real-time body data of the user and generates a personalized air supply strategy to control the ventilation module to supply air. The ventilation system has the low-energy-consumption and high-comfort ventilation effect.

The invention discloses an intelligent monitoring ventilation control method and system, an electronic device and a storage medium, and the control comprises the steps: obtaining detection data of at least two types of sensors, the different types of sensors being used for detecting different environmental data in a scene, and the detection data of the different types of sensors corresponding to different standard exceeding thresholds; judging whether at least one item of the detection data exceeds the corresponding standard exceeding threshold value or not; if yes, increasing the power of the ventilation system. According to the technical scheme provided by the invention, the technical problems that a ventilation system in the prior art cannot accurately control the power of the ventilation system and cannot timely ventilate the environment can be solved.

A ventilation hood includes a main frame which faces an appliance accessible from a front of the appliance, the main frame defining a through-hole passing through the main frame, a motor module on the main frame and configured to suck in air through the through-hole, the motor module including a duct, a motor having an axis, and an exhaust fan driven by the motor and defining a blowing direction perpendicular to the axis of the motor, and a controller configured to control operation of the ventilation hood and a rotation velocity of the exhaust fan. The axis of the motor is in a direction from the front of the appliance to a rear of the appliance which is opposite to the front. The controller is on the main frame and at a front of the duct which corresponds to the front of the appliance.