A road dust sampling method, device, terminal and storage medium

Abstract

The application relates to a road dust sampling method and device, a terminal and a storage medium, which comprises the following steps: acquiring the driving speed of a dust sampling vehicle, the first air inlet flow speed of a sampling device and the air outlet flow speed of a gas analysis equipment; adjusting the air inlet fan according to the driving speed and the first air inlet flow speed, so that the air inlet flow speed matches the driving speed; acquiring the second air inlet flow speed after adjusting the air inlet fan; adjusting the air outlet fan according to the second air inlet flow speed and the air outlet flow speed of the gas analysis equipment, so that the gas pressure in the sampling device reaches the theoretical pressure; and the theoretical pressure is set before sampling. The application has the effect of improving the accuracy of detecting dust concentration by using the vehicle-mounted walking method.

Description

Technical Field

[0001] This application relates to the field of dust detection technology, and in particular to a method, apparatus, terminal and storage medium for sampling road dust. Background Technology

[0002] The increase in urban atmospheric particulate matter is a major cause of urban haze, and road dust is one of the main sources of atmospheric particulate matter in many cities.

[0003] However, due to the large area and long routes of urban roads, as well as factors such as road damage, construction, and traffic volume, traditional dust collection and weighing methods cannot truly reflect the dust accumulation on roads, thus failing to accurately analyze the particulate matter concentration in road dust across the entire road section. Currently, vehicle-mounted mobile monitoring has become a development trend. In related technologies, to improve the accuracy of sampling data, the sampling fan speed is determined by collecting data on the vehicle's travel speed and sampling speed, thereby adjusting the gas flow rate in the intake pipe to ensure that the sampled gas concentration is close to the dust concentration at the vehicle's travel speed. However, increasing the gas flow rate in the intake pipe by the sampling fan leads to an increase in the gas pressure within the sampling device. The ideal sampling condition for the gas analysis equipment connected to the sampling device is under standard atmospheric pressure, and uneven gas pressure within the sampling device can also affect sampling accuracy. Summary of the Invention

[0004] This application provides a method, apparatus, terminal, and storage medium for sampling road dust, which improves the accuracy of detecting dust concentration using a vehicle-mounted mobile sampling method.

[0005] Firstly, this application provides a method for sampling road dust accumulation, employing the following technical solution: A method for sampling road dust includes: The driving speed of the dust sampling vehicle, the first airflow velocity at the air inlet of the sampling device, and the airflow velocity at the air outlet of the gas analysis equipment were obtained. Based on the driving speed and the first airflow speed at the air inlet, adjust the air inlet fan to match the airflow speed at the air inlet with the driving speed; Obtain the second airflow velocity at the air inlet after adjusting the air inlet fan; Based on the second airflow velocity at the air inlet and the airflow velocity at the exhaust port of the gas analysis device, the exhaust fan is adjusted to bring the gas pressure inside the sampling device to the theoretical pressure; the theoretical pressure is set before sampling.

[0006] By adopting the above technical solution, as the vehicle speed changes, the airflow velocity at the inlet is calculated to match the vehicle speed based on the vehicle speed and the first airflow velocity at the inlet. The airflow velocity in the sampling device's inlet pipe is adjusted by regulating the rotation speed of the inlet fan. When the power of the inlet fan increases, a pressure difference exists inside the sampling device. To maintain a stable gas pressure inside the sampling device, a fan is used in the outlet pipe of the sampling device for auxiliary exhaust. The outlet airflow velocity is calculated based on the second airflow velocity at the inlet and the extraction speed of the gas analysis equipment. The outlet fan is then adjusted according to the outlet airflow velocity to bring the gas pressure inside the sampling device to the theoretical pressure, thereby maintaining the gas pressure inside the sampling device and improving the accuracy of the vehicle-mounted mobile dust concentration detection method.

[0007] Optionally, based on the second airflow velocity at the inlet and the airflow velocity at the outlet of the gas analyzer, the outlet fan is adjusted to bring the gas pressure inside the sampling device to the theoretical pressure, including: The airflow velocity inside the sampling device when calculating the theoretical pressure; The theoretical airflow velocity at the inlet is calculated based on the second airflow velocity at the inlet and the airflow velocity at the exhaust port of the gas analysis device. Based on the theoretical airflow velocity at the outlet, adjust the outlet fan so that the actual airflow velocity at the outlet matches the theoretical airflow velocity.

[0008] Optionally, the airflow velocity within the sampling device when calculating the theoretical pressure includes: To obtain theoretical pressure and theoretical air density; Calculate the airflow velocity inside the sampling device at the theoretical pressure based on the theoretical pressure and theoretical air density.

[0009] Optionally, obtain the theoretical pressure and theoretical air density, including: Obtain dust sampling results collected at preset sampling points using a fixed-point sampling device; Based on the dust sampling results, the average air density of the fixed sampling section is calculated and multiplied by a preset coefficient to obtain the theoretical air density.

[0010] Optionally, based on the driving speed and the first airflow velocity at the air inlet, the air inlet fan is adjusted to match the airflow velocity at the air inlet with the driving speed, including: Obtain the inner diameter of the air inlet pipe of the sampling equipment; Based on the inner diameter of the intake pipe and the driving speed, an airflow speed matching the driving speed is obtained.

[0011] Optionally, it may also include: acquiring the actual pressure inside the sampling device; Based on the actual pressure and the theoretical pressure, adjust the outlet fan (205) to bring the actual pressure in the sampling device down to the theoretical pressure.

[0012] Secondly, this application provides a road dust sampling device, which adopts the following technical solution: A road dust sampling device, comprising: A housing, on which an air inlet pipe and an air outlet pipe are connected, and both the air inlet pipe and the air outlet pipe are connected to the housing; An air inlet fan is installed inside the air inlet duct; An air outlet fan is installed inside the air outlet duct; An inlet flow meter is used to detect the airflow velocity in the intake pipe. An outlet flow meter is used to detect the airflow velocity in an outlet pipe. A gas analysis device, wherein the gas analysis device is connected to an extraction pipe and is connected to a housing via the extraction pipe, for determining the composition of the sampled gas; A vehicle speed detector is used to detect the speed of a vehicle. An electronic barometer is used to detect the pressure inside a housing; The main controller is electrically connected to the inlet fan, the outlet fan, the inlet flow meter, the outlet flow meter, the gas analysis equipment, the vehicle speed detector, and the electronic barometer.

[0013] Optionally, the master controller is configured as follows: The driving speed of the dust sampling vehicle, the first airflow velocity at the air inlet of the sampling device, and the airflow velocity at the air outlet of the gas analysis equipment were obtained. Based on the driving speed and the first airflow speed at the air inlet, adjust the air inlet fan to match the airflow speed at the air inlet with the driving speed; Obtain the second airflow velocity at the air inlet after adjusting the air inlet fan; Based on the second airflow velocity at the air inlet and the airflow velocity at the exhaust port of the gas analysis device, the exhaust fan is adjusted to bring the gas pressure inside the sampling device to the theoretical pressure; the theoretical pressure is set before sampling.

[0014] Thirdly, this application provides a terminal that features stable transmission of encrypted data.

[0015] The aforementioned objective three of this application is achieved through the following technical solution: A terminal includes a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and executed using the aforementioned data encryption transmission method.

[0016] Fourthly, this application provides a computer storage medium capable of storing corresponding programs, which facilitates stable transmission of encrypted data.

[0017] The fourth objective of this application is achieved through the following technical solution: A computer-readable storage medium storing a computer program that can be loaded by a processor and executed by any of the above-described data encryption transmission methods.

[0018] In summary, this application includes at least one of the following beneficial technical effects: As the vehicle speed changes, the airflow velocity at the inlet is calculated to match the vehicle speed based on the vehicle speed and the first airflow velocity at the inlet, and the airflow velocity in the inlet pipe of the sampling device is adjusted by regulating the rotation speed of the inlet fan. When the power of the inlet fan increases, a pressure difference exists inside the sampling device. To maintain a stable gas pressure inside the sampling device, a fan is used in the outlet pipe of the sampling device for auxiliary exhaust. The outlet airflow velocity is calculated based on the second airflow velocity at the inlet and the extraction speed of the gas analysis equipment, and the outlet fan is adjusted according to the outlet airflow velocity to bring the gas pressure inside the sampling device to the theoretical pressure, thereby maintaining the gas pressure inside the sampling device and improving the accuracy of the vehicle-mounted mobile dust concentration detection method. Attached Figure Description

[0019] Figure 1 This is a schematic flowchart of a road dust sampling method according to one embodiment of this application.

[0020] Figure 2 This is a schematic diagram of a road dust sampling device according to one embodiment of this application.

[0021] Figure 3 This is a schematic diagram of the structure of a road dust sampling device according to one embodiment of this application.

[0022] Figure 4 This is a schematic diagram of the structure of a terminal according to an embodiment of this application.

[0023] Explanation of reference numerals in the attached drawings: 201, housing; 202, air inlet pipe; 203, air outlet pipe; 204, air inlet fan; 205, air outlet fan; 206, air inlet flow meter; 207, air outlet flow meter; 208, gas analysis equipment; 209, main controller; 210, exhaust pipe; 211, vehicle speed detector; 212, electronic barometer; 301, CPU; 302, ROM; 303, RAM; 304, bus; 305, I / O interface; 306, input section; 307, output section; 308, storage section; 309, communication section; 310, driver; 311, removable media. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] Furthermore, the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0026] The following is in conjunction with the appendix Figures 1 to 4 This application will be described in further detail.

[0027] The increase in urban atmospheric particulate matter is a major cause of urban haze. Two common methods are used to measure particulate matter concentration in urban road dust: vacuum weighing sampling and vehicle-mounted mobile sampling. Vacuum weighing sampling places the sampling device directly on the road surface to be tested, accurately measuring the amount of dust accumulated at the sampling point. Vehicle-mounted mobile sampling places the sampling device on a vehicle, which is then driven by personnel along the road surface to collect particulate matter concentration data from the entire road section. While the data collected by the vehicle-mounted mobile sampling method more closely reflects actual road conditions, its measurement accuracy is lower.

[0028] When collecting gas samples using the vehicle-mounted mobile monitoring method, to avoid the accumulation of large particles due to uneven movement of these particles in the sampling pipe inlet, the fan speed of the sampling device in the vehicle-mounted mobile monitoring system varies with the vehicle speed. This also ensures that the dust concentration in the sampled gas sample is close to that at the vehicle's travel speed, improving measurement accuracy. However, increasing the gas flow rate in the intake pipe 202 by increasing the sampling fan will increase the gas pressure inside the sampling device. Since the gas analysis equipment 208 connected to the sampling device ideally operates under standard atmospheric pressure, uneven gas pressure within the sampling device will also affect sampling accuracy.

[0029] Firstly, in order to further improve the accuracy of detecting dust concentration using the vehicle-mounted mobile sampling method, this application provides a road dust sampling method.

[0030] Reference Figure 1 A method for sampling road dust includes the following steps: S101: Obtain the driving speed of the dust sampling vehicle, the first airflow velocity at the air inlet of the sampling device, and the airflow velocity at the air extraction port of the gas analysis device 208.

[0031] In one implementation scenario, the speed of the dust sampling vehicle is typically collected by the vehicle's built-in speed detection module, or a separate speed detector 211 can be installed on the vehicle to measure its speed. The collected speed information is then transmitted to the main controller 209 via a wired or wireless connection. The speed detection module or speed detector 211 can be a wireless positioning device such as the BeiDou Navigation Satellite System, used to measure the vehicle's speed. The main controller 209 can employ a microprocessor unit such as a single-chip microcomputer, capable of receiving the vehicle speed information collected by the speed detection module or speed detector 211.

[0032] In one implementation scenario, the second airflow velocity at the air inlet of the sampling device is determined by an electronic flow meter installed on the air inlet pipe 202 of the sampling device, which measures the first airflow velocity at the air inlet of the air inlet of the air inlet 202 and transmits it to the main controller 209 via a wired or wireless connection.

[0033] In one implementation scenario, the airflow velocity at the extraction port of the gas analyzer 208 is set at the factory. Different models of gas analyzers 208 have different extraction velocities, and some gas analyzers 208 also have adjustable extraction velocities. Before using the sampling device, the sampling personnel can manually set the extraction velocity of the gas analyzer 208 and input this extraction velocity as the airflow velocity at the extraction port into the sampling device. Alternatively, the extraction velocity of the gas analyzer 208 can be adjusted by a script, or the extraction velocity of the gas analyzer 208 can be directly read by a script and input as the airflow velocity at the extraction port into the main controller 209.

[0034] S102: Based on the driving speed and the first airflow speed at the air inlet, the air inlet fan 204 matches the airflow speed at the air inlet with the driving speed.

[0035] Specifically, the speed of a car is usually considered to be the airflow speed when there is no wind in the current environment. Therefore, when the speed is converted to meters per second, this speed can be considered as the air intake speed that the sampling device's air intake pipe 202 needs to reach. Then, by multiplying the air intake speed by the inner diameter of the air intake pipe 202, the theoretical airflow speed at the air intake can be obtained.

[0036] In one implementation scenario, the power of the intake fan 204 is gradually increased or decreased by the main controller 209 to adjust the rotational speed of the intake fan 204, thereby gradually adjusting the first airflow velocity at the intake to the theoretical airflow velocity. For example, when the car accelerates, if the first airflow velocity at the intake is less than the theoretical airflow velocity, the main controller 209 makes a comparison and outputs a command to gradually increase the power of the intake fan 204. The airflow velocity at the intake after adjusting the intake fan 204 is recorded as the second airflow velocity at the intake. When the second airflow velocity matches the theoretical airflow velocity, a command to maintain the power of the intake fan 204 is output. In this step, matching the intake airflow velocity with the driving speed means that, within the allowable error range, the intake airflow velocity, i.e., the second airflow velocity at the intake, reaches a preset range of the driving speed value; this is considered a successful match.

[0037] In another implementation scenario, a calculation method can be used to adjust the rotational speed of the intake fan 204. When using this method, the specifications of the fan inside the intake duct 202 need to be input into the main controller 209 beforehand to calculate the proportional coefficient between the fan speed and the airflow velocity inside the intake duct 202. When the vehicle's speed changes, the rotational speed of the intake fan 204 is derived based on the theoretical airflow velocity at the intake and the proportional coefficient. Then, the power of the intake fan 204 is calculated using the power-speed relationship in its specifications. Finally, the main controller 209 outputs an adjustment command to adjust the intake fan 204 to the specified power, thereby achieving a match between the airflow velocity at the intake and the vehicle's speed.

[0038] S103: Adjust the outlet fan 205 to bring the gas pressure inside the sampling device to the theoretical pressure based on the second airflow velocity at the inlet and the airflow velocity at the outlet of the detector.

[0039] The ideal sampling condition for the gas analysis equipment 208 connected to the sampling device is under standard atmospheric pressure. As the vehicle speed increases, the power of the intake fan 204 also increases, resulting in a pressure difference inside the sampling device, which may affect the sampling results of the gas analysis equipment 208. Therefore, in order to maintain a stable gas pressure inside the sampling device, a fan is used in the outlet pipe 203 of the sampling device for auxiliary exhaust. The gas pressure inside the sampling device is adjusted to the theoretical pressure by adjusting the outlet fan 205.

[0040] Specifically, the concentration of particulate matter in a gas affects its density, which in turn affects its pressure. Therefore, calculations cannot be performed using standard atmospheric pressure. Furthermore, due to significant speed variations during the initial sampling phase of a mobile sampling system and the period following vehicle start-up, dust concentrations may be extremely low at start-up but rapidly increase after sudden acceleration. Therefore, a theoretical density value is needed to replace the actual data in the calculations.

[0041] In one implementation scenario, it is first necessary to estimate the approximate concentration of particulate matter in the air of the street to be measured. The method used in this application is to collect the amount of dust accumulated at predetermined points on the street to be measured using a dust collection and weighing method. These predetermined points can be evenly distributed along the road to be measured, or selected according to the actual conditions of the road segment to be measured. Then, the results of the fixed-point dust sampling are obtained, along with the coefficient between the dust accumulation and dust concentration calculated from historical detection data. The theoretical air density is calculated based on the results of the fixed-point dust sampling and the predetermined coefficient. One specific calculation method involves: removing erroneous values ​​from the fixed-point sampling results, such as removing the maximum and minimum values; then calculating the average dust accumulation on the road to be measured; and finally multiplying the average dust accumulation by the predetermined coefficient to obtain the theoretical air density.

[0042] After obtaining the theoretical air density in the aforementioned real-time scenario, the theoretical pressure inside the sampling device is then calculated. The theoretical pressure takes into account the influence of gas flow on pressure, combining standard atmospheric pressure with an error threshold to obtain the theoretical pressure.

[0043] Furthermore, by using the theoretical air density and theoretical pressure, the range of airflow velocity within the sampling device can be calculated according to the total pressure formula for flowing gas. To ensure that the airflow velocity within the sampling device is within the calculated range, it is necessary to calculate the theoretical airflow velocity at the outlet and adjust the outlet fan 205 accordingly. Therefore, an electronic flow meter needs to be installed in the outlet pipe 203 to accurately obtain the airflow velocity at the outlet, and the electronic flow meter in the outlet pipe 203 is electrically connected to the main controller 209. Then, since the total amount and pressure of the gas flowing through the sampling device are constant, under these conditions, the gas entering the sampling device through the inlet pipe 202 has only two destinations: part of it is drawn away by the gas analysis device 208, and the other part is discharged through the outlet pipe 203. Since the gas analysis device 208 has a fixed drawing speed, the theoretical airflow velocity at the outlet can be calculated based on the airflow velocity at the inlet. Finally, using the same method as in step S102, the outlet fan 205 is adjusted to bring the gas pressure within the sampling device to the theoretical pressure.

[0044] S104: Correct the data based on the results from the sampling device.

[0045] In one implementation scenario, since the gas density used during the initial stage of the car's calculation process is estimated using a fixed-point sampling method, there is an error compared to the actual gas density. Therefore, during the driving process, it is necessary to correct the gas density based on the analysis data from the gas analysis device 208 to further reduce the error.

[0046] In one implementation scenario, the main controller 209 receives gas sampling and analysis data from the gas analysis device 208; the gas sampling and analysis data includes parameters such as gas density and particulate matter concentration. Then, the main controller 209 recalculates the pressure inside the sampling device based on the gas density in the gas sampling and analysis data, and records it as the actual pressure. Finally, based on the actual pressure, the method in step S103 is repeated to adjust the outlet fan 205 to bring the gas pressure inside the sampling device to the actual pressure.

[0047] In another implementation scenario, the actual pressure inside the sampling device can be directly detected using the electronic barometer 212. However, the method of measuring the actual air pressure and then adjusting the outlet fan 205 has a time lag, which is not suitable for real-time changing measurement environments. Therefore, using the electronic barometer 212 to obtain the actual air pressure is more suitable for small-scale data correction.

[0048] In summary, the beneficial effects of the method in this application are as follows: As the vehicle speed changes, the airflow velocity at the inlet is calculated to match the vehicle speed based on the vehicle speed and the first airflow velocity at the inlet. The airflow velocity in the inlet pipe 202 of the sampling device is adjusted by regulating the rotation speed of the inlet fan 204. When the power of the inlet fan 204 increases, a pressure difference exists inside the sampling device. To maintain a stable gas pressure inside the sampling device, a fan is used in the outlet pipe of the sampling device for auxiliary exhaust. The outlet airflow velocity is calculated based on the second airflow velocity at the inlet and the extraction speed of the gas analysis device 208. The outlet fan 205 is adjusted according to the outlet airflow velocity to bring the gas pressure inside the sampling device to the theoretical pressure, thereby maintaining the gas pressure inside the sampling device and improving the accuracy of the vehicle-mounted mobile dust concentration detection method.

[0049] Secondly, this application provides a road dust sampling device, which adopts the following technical solution: Reference Figure 2 and Figure 3 A road dust sampling device, comprising: The housing 201 is connected to an inlet pipe 202 and an outlet pipe 203, both of which are connected to the housing 201. An inlet fan 204 and an inlet flow meter 206 are installed inside the inlet pipe 202, and an outlet fan 205 and an outlet flow meter 207 are installed inside the outlet pipe 203. The inlet flow meter 206 is used to detect the airflow velocity in the inlet pipe 202; the outlet flow meter 207 is used to detect the airflow velocity in the outlet pipe 203. Both the inlet flow meter 206 and the outlet flow meter 207 are electronic flow meters.

[0050] To perform real-time analysis of the collected gas samples, a gas analysis device 208 is also connected to the housing 201. The gas analysis device 208 is connected to the housing 201 via a gas extraction pipe 210 and is used to determine the composition of the sampled gas. In this application, the gas analysis device 208 is a particulate matter sensor or a gas analyzer.

[0051] To determine the speed of the sampling vehicle, a vehicle speed detector 211 is also included. The vehicle speed detector 211 can be a positioning device such as the Beidou system, used to measure the speed of the sampling vehicle. The vehicle speed detector 211 can directly use the vehicle speed detection module on the sampling vehicle, or the vehicle speed detector 211 can be installed separately on the vehicle.

[0052] To refine the calculation results, an electronic barometer 212 is also included. The electronic barometer 212 can detect the pressure inside the housing and send the pressure data to the main controller.

[0053] The main controller 209 is electrically connected to the inlet fan 204, the outlet fan 205, the inlet flow meter 206, the outlet flow meter 207, the gas analysis equipment 208, the vehicle speed detector 211, and the electronic barometer 212, respectively, and is used to perform functions such as... Figure 1 The method shown.

[0054] Figure 4 A schematic diagram of a terminal suitable for implementing embodiments of this application is shown.

[0055] like Figure 4As shown, the terminal includes a Central Processing Unit (CPU) 301, which can perform various appropriate actions and processes based on programs stored in Read-Only Memory (ROM) 302 or programs loaded from storage into Random Access Memory (RAM) 303. The RAM 303 also stores various programs and data required for system operation. The CPU 301, ROM 302, and RAM 303 are interconnected via a bus 304. An Input / Output (I / O) interface 305 is also connected to the bus 304.

[0056] The following components are connected to I / O interface 305: an input section 306 including a keyboard, mouse, etc.; an output section 307 including a cathode ray tube (CRT), liquid crystal display (LCD), and speakers, etc.; a storage section 308 including a hard disk, etc.; and a communication section 309 including a network interface card such as a LAN card and a modem, etc. The communication section 309 performs communication processing via a network such as the Internet. A drive 310 is also connected to I / O interface 305 as needed. A removable medium 311, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 310 as needed so that computer programs read from it can be installed into storage section 308 as needed.

[0057] Specifically, according to embodiments of this application, the above reference flow Figure 1 The described process can be implemented as a computer software program. For example, embodiments of this application include a computer program product comprising a computer program carried on a machine-readable medium, the computer program containing program code for performing the methods shown in the flowchart. In such embodiments, the computer program can be downloaded and installed from a network via communication section 309, and / or installed from removable medium 311. When the computer program is executed by central processing unit (CPU) 301, it performs the functions defined in the system of this application.

[0058] It should be noted that the computer-readable medium shown in this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. The transmitted data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wireless, wire, optical fiber, register file (RF), etc., or any suitable combination thereof.

[0059] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0060] The units or modules described in the embodiments of this application can be implemented in software or hardware. The described units or modules can also be located in a processor. The names of these units or modules do not, in certain circumstances, constitute a limitation on the unit or module itself.

[0061] In another aspect, this application also provides a computer-readable storage medium, which may be included in the terminal described in the above embodiments; or it may exist independently and not assembled into the terminal. The aforementioned computer-readable storage medium stores one or more programs, which are used by one or more processors to execute the data encryption transmission method described in this application.

[0062] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of disclosure in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the foregoing disclosed concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A method for sampling road dust, characterized in that, include: The driving speed of the dust sampling vehicle, the first airflow velocity at the air inlet of the sampling device, and the airflow velocity at the air outlet of the gas analysis device (208) are obtained. Based on the driving speed and the first airflow velocity at the air inlet, adjust the air inlet fan (204) so ​​that the airflow velocity at the air inlet matches the driving speed; Obtain the second airflow velocity at the inlet after adjusting the inlet fan (204); The airflow velocity inside the sampling device is used to calculate the theoretical pressure; the theoretical pressure is set before sampling. The theoretical airflow velocity at the air inlet is calculated based on the second airflow velocity at the air inlet and the airflow velocity at the exhaust port of the gas analysis device (208). Based on the theoretical airflow velocity at the outlet, adjust the outlet fan (205) so that the actual airflow velocity at the outlet is consistent with the theoretical airflow velocity at the outlet.

2. The road dust sampling method according to claim 1, characterized in that, The calculation of the airflow velocity inside the sampling device at the theoretical pressure includes: obtaining the theoretical pressure and theoretical air density; and calculating the airflow velocity inside the sampling device at the theoretical pressure based on the theoretical pressure and theoretical air density.

3. The road dust sampling method according to claim 2, characterized in that, Obtaining the theoretical air density includes: obtaining dust sampling results collected at preset sampling points using a fixed-point sampling device; calculating the average air density of the fixed-point sampling section based on the dust sampling results and multiplying it with a preset coefficient to obtain the theoretical air density.

4. The road dust sampling method according to claim 1, characterized in that, Based on the driving speed and the first airflow velocity at the air inlet, the air inlet fan (204) is adjusted to match the airflow velocity at the air inlet with the driving speed, including: obtaining the inner diameter of the sampling device air inlet pipe (202); and obtaining an airflow velocity that matches the driving speed based on the inner diameter of the air inlet pipe (202) and the driving speed.

5. The road dust sampling method according to claim 1, characterized in that, Also includes: Obtain the actual pressure inside the sampling device; Based on the actual pressure and the theoretical pressure, adjust the outlet fan (205) to bring the actual pressure in the sampling device down to the theoretical pressure.

6. A road dust sampling device, characterized in that, include: A housing (201) is provided with an air inlet pipe (202) and an air outlet pipe (203) connected to the housing (201), and both the air inlet pipe (202) and the air outlet pipe (203) are connected to the housing (201). An air inlet fan (204) is installed inside an air inlet pipe (202); An air outlet fan (205) is installed inside an air outlet pipe (203); An inlet flow meter (206) is used to detect the airflow velocity in the inlet pipe (202); An outlet flow meter (207) is used to detect the airflow velocity in the outlet pipe (203); A gas analysis device (208) is connected to an extraction pipe (210). The gas analysis device (208) is connected to the housing (201) through the extraction pipe (210) and is used to determine the composition of the sampled gas. Vehicle speed detector (211) is used to detect the speed of a vehicle. Electronic barometer (212) is used to detect the pressure inside the housing; The main controller (209) is electrically connected to the inlet fan (204), the outlet fan (205), the inlet flow meter (206), the outlet flow meter (207), the gas analysis equipment (208), the vehicle speed detector (211), and the electronic barometer (212). The main controller (209) is configured as follows: The driving speed of the dust sampling vehicle, the first airflow velocity at the air inlet of the sampling device, and the airflow velocity at the air outlet of the gas analysis device (208) are obtained. Based on the driving speed and the first airflow velocity at the air inlet, adjust the air inlet fan (204) so ​​that the airflow velocity at the air inlet matches the driving speed; Obtain the second airflow velocity at the inlet after adjusting the inlet fan (204); The airflow velocity inside the sampling device is used to calculate the theoretical pressure; the theoretical pressure is set before sampling. The theoretical airflow velocity at the air inlet is calculated based on the second airflow velocity at the air inlet and the airflow velocity at the exhaust port of the gas analysis device (208). Based on the theoretical airflow velocity at the outlet, adjust the outlet fan (205) so that the actual airflow velocity at the outlet is consistent with the theoretical airflow velocity at the outlet.

7. A terminal comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the program, it implements the method as described in any one of claims 1 to 5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1 to 5.

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