CN114398821A - Sewage treatment analysis and control method based on data mining and intelligent algorithm - Google Patents

Sewage treatment analysis and control method based on data mining and intelligent algorithm Download PDF

Info

Publication number
CN114398821A
CN114398821A CN202111522150.5A CN202111522150A CN114398821A CN 114398821 A CN114398821 A CN 114398821A CN 202111522150 A CN202111522150 A CN 202111522150A CN 114398821 A CN114398821 A CN 114398821A
Authority
CN
China
Prior art keywords
sewage treatment
cps
instrument
control unit
water outlet
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202111522150.5A
Other languages
Chinese (zh)
Inventor
余庆
许娟
杨帆
吴蜀青
李意林
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dewen Environmental Protection Technology Co ltd
Original Assignee
Dewen Environmental Protection Technology Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dewen Environmental Protection Technology Co ltd filed Critical Dewen Environmental Protection Technology Co ltd
Priority to CN202111522150.5A priority Critical patent/CN114398821A/en
Publication of CN114398821A publication Critical patent/CN114398821A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00Computer-aided design [CAD]
    • G06F30/20Design optimisation, verification or simulation
    • G06F30/27Design optimisation, verification or simulation using machine learning, e.g. artificial intelligence, neural networks, support vector machines [SVM] or training a model
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06QINFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q50/00Information and communication technology [ICT] specially adapted for implementation of business processes of specific business sectors, e.g. utilities or tourism
    • G06Q50/06Energy or water supply
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F2119/00Details relating to the type or aim of the analysis or the optimisation
    • G06F2119/02Reliability analysis or reliability optimisation; Failure analysis, e.g. worst case scenario performance, failure mode and effects analysis [FMEA]

Landscapes

  • Engineering & Computer Science (AREA)
  • Business, Economics & Management (AREA)
  • Theoretical Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Evolutionary Computation (AREA)
  • Health & Medical Sciences (AREA)
  • Economics (AREA)
  • Tourism & Hospitality (AREA)
  • General Health & Medical Sciences (AREA)
  • Geometry (AREA)
  • Feedback Control In General (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Public Health (AREA)
  • Computer Hardware Design (AREA)
  • Software Systems (AREA)
  • Water Supply & Treatment (AREA)
  • General Engineering & Computer Science (AREA)
  • Human Resources & Organizations (AREA)
  • Marketing (AREA)
  • Primary Health Care (AREA)
  • Strategic Management (AREA)
  • Artificial Intelligence (AREA)
  • General Business, Economics & Management (AREA)
  • Medical Informatics (AREA)

Abstract

The invention relates to the field of sewage treatment, and provides a sewage treatment analysis and control method based on data mining and intelligent algorithm, wherein a sewage treatment terminal is provided with a meteorological data acquisition system, a water inlet COD (chemical oxygen demand) instrument, a TN (twisted nematic) instrument, a pH meter, a thermometer, a water inlet flow meter, an ORP (oxidation-reduction potential) instrument, an outlet water online monitor, a plurality of pumps, a plurality of dosing devices and a plurality of blowers, a central control system and a CPS (physical control system) micro-control unit are established, an information physical system which is trained based on a large amount of sewage treatment plant operation data establishment algorithm model is pre-stored in the central control system and the field CPS micro-control unit, various instrument parameters are used as the input of the information physical system, the output of the information physical system is a corresponding operation instruction, the pumps, the dosing devices and the blowers are driven by the operation instruction, the target working time and power are achieved, the central control system also sends an upper layer control and decision strategy to the CPS micro-control unit through a communication module, and feeding back various control parameters of the sewage treatment terminal.

Description

Sewage treatment analysis and control method based on data mining and intelligent algorithm
Technical Field
The invention relates to the technical field of sewage treatment in villages and towns and rural areas, in particular to a sewage treatment analysis and control method based on data mining and intelligent algorithms.
Background
According to different regional conditions of rural areas, the gathering degree of village population and the scale of sewage generation, a construction mode and a treatment process combining pollution control and resource utilization, engineering measures and ecological measures and concentration and dispersion are adopted according to local conditions.
Based on the characteristics of wide rural distribution, dispersed inhabitants of farmers, large fluctuation of water quantity and water quality and the like in China. Aiming at the problems of insufficient construction of rural infrastructure, imperfect sewage collecting and conveying pipe network, generally low personnel culture level, weak operation and management capability and the like, the novel technology for treating sewage in rural areas in China is developed, and the novel technology has the characteristics of low investment, low energy consumption, simplicity in operation and maintenance, high pollutant removal efficiency and the like, so that the novel technology is not only an urgent need for survival and development of enterprises, but also an urgent need for healthy development of rural sewage treatment industry and realization of beautiful rural areas. CPS micro control unit
Disclosure of Invention
The invention aims to provide a sewage treatment analysis and control method based on data mining and intelligent algorithm, wherein an information physical system which is trained based on an algorithm model established by running data of a large number of sewage treatment plants is prestored in a central control system and a field CPS Microcontroller-Unit (CPSM), various instrument parameters are used as the input of the information physical system, the output of the information physical system is a corresponding operating instruction, and a pump, a dosing device and a blower are driven by the operating instruction, so that the working target time length and power are obtained.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a sewage treatment analysis and control method based on data mining and intelligent algorithm, a sewage treatment terminal is provided with a meteorological data acquisition system, a water inlet COD instrument, a TN instrument, a pH meter, a thermometer, a water inlet flow meter, an ORP instrument, a water outlet online monitor, a plurality of pumps, a plurality of dosing devices and a plurality of air blowers, a central control system is established, the instruments are connected to a CPS micro control unit, the meteorological data acquisition system, the water inlet COD instrument, the TN instrument, the pH meter, the thermometer, the water inlet flow meter, the ORP instrument and the water outlet online monitor are connected with the CPS micro control unit, the CPS micro control unit is connected with the pumps, the dosing devices and the air blowers, the CPS micro control unit is connected with the central control system through a communication module and a network,
the CPS micro control unit and the central control system are pre-stored with trained neural network prediction models, parameters of various instruments are used as input of the neural network prediction models, output of the neural network prediction models is corresponding operation instructions, the operation instructions drive target working time length and power of a pump, a dosing machine, a blower and the like, the CPS micro control unit is further connected with a communication module, and data of various instruments of the sewage treatment terminal are sent to the mobile terminal through the communication module.
Preferably, the system comprises a meteorological data acquisition system, a water inlet COD (chemical oxygen demand) instrument, a TN (twisted nematic) instrument, a pH meter, a thermometer, a water inlet flowmeter, an ORP (oxidation-reduction potential) instrument and a water outlet online monitor, wherein the CPS micro control unit respectively acquires nine variable signals with independent adjustment periods and adjustment amplitudes, namely meteorological data, a water inlet COD value, a pH value of a sewage treatment terminal, a sewage treatment terminal temperature, an ORP (oxidation-reduction potential), a water outlet COD value, a water outlet ammonia nitrogen value, a water outlet TN (twisted nematic) value and a water outlet total phosphorus value.
Preferably, the neural network prediction model comprises an input layer, a hidden layer, a connection layer and an output layer, wherein the trained neural network prediction model is obtained by training a transmission function of the connection layer through synchronous historical data.
Preferably, the training content of the connection layer includes the following steps:
step S1: collecting four variable signals and fault alarm state values in a T0 time period, wherein the T0 time period comprises a plurality of unit time T, counting the four variable signals in the unit time according to a time sequence in the fault alarm state, and sending the four variable signals to the step S2;
step S2: performing regression calculation on the four variable signals in the multiple fault alarm states to obtain a linear relation of the four variable signals in unit time;
step S3: the water quality inlet COD value, the sewage treatment terminal pH value, the sewage treatment terminal temperature, the ORP, the outlet COD value, the outlet ammonia nitrogen value, the outlet TN value, the outlet total phosphorus value and the operation instructions of a pump, a dosing machine and a blower are subjected to data mining and analysis to obtain a trained nonlinear function of the connecting layer.
Preferably, the pump, the dosing machine, the blower and other equipment are driven to work under corresponding rotating speed and power through different operation commands, the operation commands are decomposed into different emergency degree grades from low to high, and the higher the emergency degree grade is, the higher the power of the corresponding pump, dosing machine and blower is.
Preferably, the judging standard of the emergency degree grade sent by the CPS micro-control unit comprises a first-level A standard, a first-level B standard and other settable discharge standards, and the target values of COD, ammonia nitrogen, TN and TP control in the first-level A standard are smaller than the target values of COD, ammonia nitrogen, TN and TP control in the first-level B standard.
In conclusion, the beneficial effects of the invention are as follows:
1. the automatic adjustment of the treatment process parameters is carried out according with the technical means of the sewage treatment process, so that the system can always keep the treatment process of pollutants in the sewage in the optimal state according with the sewage treatment process and meet the effluent standard on the premise of not needing manual intervention. The process parameters include, but are not limited to: the biochemical reaction aeration time and intensity, the residual sludge discharge amount, the sludge reflux amount and the dosage;
2. the process trend is predicted based on the Elman neural network. The basic Elman neural network consists of an input layer, a hidden layer, a connection layer and an output layer. There is a connection layer for constituting a local feedback. The transmission function of the connection layer is a linear function, but one more delay unit is added, so that the connection layer can memorize the past state and can be used as the input of the hidden layer together with the input of the network at the next moment, so that the network has a dynamic memory function;
drawings
FIG. 1 is a schematic diagram of a sewage treatment analysis and control method based on data mining and intelligent algorithm according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below with reference to fig. 1 of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1:
a sewage treatment analysis and control method based on data mining and intelligent algorithm, a sewage treatment terminal is provided with a meteorological data acquisition system, a water inlet COD instrument, a TN instrument, a pH meter, a thermometer, a water inlet flow meter, an ORP instrument, a water outlet online monitor, a plurality of pumps, a plurality of dosing devices and a plurality of air blowers, a central control system is established, the instruments are connected to a CPS micro control unit, the meteorological data acquisition system, the water inlet COD instrument, the TN instrument, the pH meter, the thermometer, the water inlet flow meter, the ORP instrument and the water outlet online monitor are connected with the CPS micro control unit, the CPS micro control unit is connected with the pumps, the dosing devices and the air blowers, the CPS micro control unit is connected with the central control system through a communication module and a network,
the System comprises a central control System and a field CPS micro control unit, wherein a Cyber-Physical System (CPS) which is trained based on a large amount of sewage treatment plant operation data establishment algorithm model is prestored in the central control System and the field CPS micro control unit, various instrument parameters are used as input of the Cyber-Physical System, output of the Cyber-Physical System is corresponding operation instructions, a plurality of pumps, a plurality of dosing devices and a plurality of blowers are driven through the operation instructions, and the CPS micro control unit is connected with a communication module, and various instrument data, abnormality identification and diagnosis data of a sewage treatment terminal and control and decision strategies obtained through data mining, fuzzy algorithm and artificial intelligence are sent to the central control System and a mobile terminal through the communication module. The central control system also sends the upper control and decision strategy to the CPS micro-control unit through the communication module, and feeds back and controls various control parameters of the sewage treatment terminal.
The system comprises a meteorological data acquisition system, a water inlet COD (chemical oxygen demand) instrument, a TN (twisted nematic) instrument, a pH meter, a thermometer, a water inlet flowmeter, an ORP (oxidation-reduction potential) instrument and a water outlet online monitor, wherein the CPS micro control unit respectively acquires nine variable signals with independent regulation periods and regulation amplitudes, namely meteorological data, a water inlet COD (chemical oxygen demand) value, a sewage treatment terminal pH value, a sewage treatment terminal temperature, an ORP (oxidation-reduction potential), a water outlet COD (chemical oxygen demand) value, a water outlet ammonia nitrogen value, a water outlet TN (total phosphorus value) and a water outlet total phosphorus value.
The neural network prediction model comprises an input layer, a hidden layer, a connection layer and an output layer, wherein the trained neural network prediction model is obtained by training a transmission function of the connection layer through synchronous historical data.
The training content of the connection layer comprises the following steps:
step S1: collecting four variable signals and fault alarm state values in a T0 time period, wherein the T0 time period comprises a plurality of unit time T, counting the four variable signals in the unit time according to a time sequence in the fault alarm state, and sending the four variable signals to the step S2;
step S2: performing regression calculation on the four variable signals in the multiple fault alarm states to obtain a linear relation of the four variable signals in unit time;
it should be noted that the four variable signal values include time (accurate to minute, including weather and temperature of the day), characteristic parameters, corresponding states (including whether failure occurs) under the characteristic parameters, and required interval values of the characteristic parameters (combined with the set interval of the day), the four variable signals are calculated, the positive scores of the satisfied intervals are calculated, the negative scores of the unsatisfied intervals are calculated, and the total scores of the single characteristic parameters of the day are calculated and summarized.
Step S3: and combining the temperature parameter of the water quality and the operation instruction of the blower in the T0 time period, and combining the linear relation in unit time to obtain the trained linear function of the connecting layer. Referring to fig. 1, the present application further adopts data methods such as a fuzzy algorithm, etc. to train the variable signal, obtain an optimal sewage treatment control model, obtain a linear relationship between a single characteristic parameter and the sewage treatment control model, and form an evaluation system for sewage treatment.
The CPS micro-control unit sends out judgment standards of the emergency degree grade, wherein the judgment standards comprise a first-level A standard, a first-level B standard and other settable discharge standards, and the target values of COD, ammonia nitrogen, TN and TP control in the first-level A standard are smaller than the target values of COD, ammonia nitrogen, TN and TP control in the first-level B standard.
It should be noted that, referring to fig. 1, in this embodiment, when a sewage treatment system having a plurality of sewage treatment terminals is used, statistics of total scores of characteristic parameters is performed according to types of different sewage treatment terminals, it is considered that sewage containers of different sizes and shapes affect the characteristic parameters in water quality, and in order to obtain more objective characteristic parameters, correlation is performed with sewage treatment efficiency, so that the types of specific sewage containers are matched, and it is noted that the sewage treatment efficiency in this embodiment is characterized by being set to an emergency degree grade, a total score of characteristic parameters, and a treatment speed of sewage per cubic meter (a ratio of a volume of a sewage container to a difference between water outlet time and water inlet time).

Claims (6)

1. A sewage treatment analysis and control method based on data mining and intelligent algorithm is characterized in that a sewage treatment terminal is provided with a meteorological data acquisition system, a water inlet COD (chemical oxygen demand) instrument, a TN (twisted nematic) instrument, a pH meter, a thermometer, a water inlet flow meter, an ORP (oxidation-reduction potential) instrument, a water outlet online monitor, a plurality of pumps, a plurality of dosing devices and a plurality of air blowers, a central control system is established, the instruments are connected to a CPS (physical control system) micro control unit, the meteorological data acquisition system, the water inlet COD instrument, the TN instrument, the pH meter, the thermometer, the water inlet flow meter, the ORP instrument and the water outlet online monitor are connected with the CPS micro control unit, the CPS micro control unit is connected with the pumps, the dosing devices and the air blowers, and the CPS micro control unit is connected with the central control system through a communication module and a network.
The CPS micro control unit and the central control system are pre-stored with trained neural network prediction models, parameters of various instruments are used as input of the neural network prediction models, output of the neural network prediction models is corresponding operation instructions, the operation instructions drive target working time length and power of a pump, a dosing machine, a blower and the like, the CPS micro control unit is further connected with a communication module, and data of various instruments of the sewage treatment terminal are sent to the mobile terminal through the communication module.
2. The method for analyzing and controlling sewage treatment based on data mining and intelligent algorithm according to claim 1, wherein the meteorological data acquisition system, the water inlet COD meter, the TN meter, the pH meter, the thermometer, the water inlet flow meter, the ORP meter and the water outlet on-line monitor, the CPS micro control unit respectively acquires nine variable signals with independent adjustment period and adjustment amplitude, namely meteorological data, water inlet COD value, sewage treatment terminal pH value, sewage treatment terminal temperature, ORP, water outlet COD value, water outlet ammonia nitrogen value, water outlet TN value and water outlet total phosphorus value.
3. The method of claim 2, wherein the neural network prediction model comprises a service layer, an input layer, an application layer, a hidden layer, a connection layer and an output layer, and wherein the trained neural network prediction model is obtained by training a transmission function of the connection layer through synchronous historical data.
4. The method for analyzing and controlling sewage treatment based on data mining and intelligent algorithm of claim 3, wherein the training content of the connection layer comprises the following steps:
step S1: collecting nine variable signals and fault alarm state values in a T0 time period, wherein the T0 time period comprises a plurality of unit time T, counting the nine variable signals in the unit time according to a time sequence in the fault alarm state, and sending the nine variable signals to the step S2;
step S2: performing regression calculation on the nine variable signals in the multiple fault alarm states to obtain a linear relation of the nine variable signals in unit time;
step S3: and in combination with the water inlet COD value, the sewage treatment terminal pH value, the sewage treatment terminal temperature, the ORP, the water outlet COD value, the water outlet ammonia nitrogen value, the water outlet TN value, the water outlet total phosphorus value and the operation instructions of the pump, the dosing machine and the blower of the water quality in the T0 time period, obtaining the trained nonlinear function of the connecting layer through data mining and analysis.
5. The method for analyzing and controlling sewage treatment based on data mining and intelligent algorithm according to claim 1, wherein different operation commands are used for driving equipment such as pumps, dosing machines and blowers to work at corresponding rotating speeds and powers, the operation commands are decomposed into different urgency levels from low to high, and the higher the urgency level is, the higher the power of the corresponding pumps, dosing machines and blowers is.
6. The method as claimed in claim 5, wherein the criteria for determining the level of urgency sent by the CPS micro-control unit include a primary A standard, a primary B standard and other settable discharge standards, and the target values of COD, ammonia nitrogen, TN and TP in the primary A standard are less than those in the primary B standard.
CN202111522150.5A 2021-12-13 2021-12-13 Sewage treatment analysis and control method based on data mining and intelligent algorithm Pending CN114398821A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111522150.5A CN114398821A (en) 2021-12-13 2021-12-13 Sewage treatment analysis and control method based on data mining and intelligent algorithm

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111522150.5A CN114398821A (en) 2021-12-13 2021-12-13 Sewage treatment analysis and control method based on data mining and intelligent algorithm

Publications (1)

Publication Number Publication Date
CN114398821A true CN114398821A (en) 2022-04-26

Family

ID=81226393

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111522150.5A Pending CN114398821A (en) 2021-12-13 2021-12-13 Sewage treatment analysis and control method based on data mining and intelligent algorithm

Country Status (1)

Country Link
CN (1) CN114398821A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117764332A (en) * 2023-12-19 2024-03-26 广东精英纺织服饰科技有限公司 Environment-friendly and efficient textile printing and dyeing wastewater treatment system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109607632A (en) * 2018-12-25 2019-04-12 湖南智水环境设备有限公司 The control system of sewage disposal device
CN110889085A (en) * 2019-09-30 2020-03-17 华南师范大学 Intelligent wastewater monitoring method and system based on complex network multiple online regression
CN111847634A (en) * 2020-07-10 2020-10-30 北控水务(中国)投资有限公司 Aeration and carbon source adding optimization control system and method for sludge-membrane composite sewage treatment process

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109607632A (en) * 2018-12-25 2019-04-12 湖南智水环境设备有限公司 The control system of sewage disposal device
CN110889085A (en) * 2019-09-30 2020-03-17 华南师范大学 Intelligent wastewater monitoring method and system based on complex network multiple online regression
CN111847634A (en) * 2020-07-10 2020-10-30 北控水务(中国)投资有限公司 Aeration and carbon source adding optimization control system and method for sludge-membrane composite sewage treatment process

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
马邕文等: "模糊神经模型对废水处理过程COD的预测及控制", 《中国造纸学报》 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117764332A (en) * 2023-12-19 2024-03-26 广东精英纺织服饰科技有限公司 Environment-friendly and efficient textile printing and dyeing wastewater treatment system

Similar Documents

Publication Publication Date Title
CN109879474B (en) Dynamic adjustment type sewage working condition treatment system
CN109879475B (en) Dynamic adjustment type sewage working condition treatment method
CN111362328B (en) Dynamic optimal scheduling system and method for sewage treatment facility based on water quality and water quantity
CN202054663U (en) Dissolved oxygen automatic control system for sewage water biological pool
CN111596621A (en) Intelligent water affair on-line monitoring, control and management system of thermal power plant
CN104777811A (en) Novel integrated environmental protection equipment based on mobile IoT (Internet of Things)
CN106495321A (en) Biological tank process optimization and operation control system and its control method
CN114398821A (en) Sewage treatment analysis and control method based on data mining and intelligent algorithm
CN113759832A (en) Intelligent operation method for sewage plant
CN202808475U (en) Surface aeration energy-saving control device
CN111708339A (en) Artificial intelligence control system and method for sewage plant and application of artificial intelligence control system
CN214693460U (en) Ozone dosing control system in advance
KR20030041652A (en) Control apparatus for sewage and wastewater equipment
CN111777138A (en) Sewage treatment refined control system and control method based on Internet of things
CN214623362U (en) Sewage pipe network dispatching system
CN102053615A (en) Unsteady-state sectional influent water depth nitrogen and phosphorus removal process control system and control method
JP2003245653A (en) Operation supporting method for treatment system, operation supporting method for water treatment system and equipment therefor
CN207380527U (en) A kind of sewage disposal automatic control system
CN111847628A (en) Water treatment control system and method
CN207845269U (en) constant DO control system based on real-time OUR
CN117274008A (en) Sewage treatment analysis control method integrating multiple algorithms
CN201864645U (en) Sewage treatment recycling device capable of being monitored
CN212655595U (en) Automatic control system for water quality of high-level water collecting cooling tower of thermal power plant
CN1614524A (en) Computer controlling system of urban sewage treatment based on dispersing and distributing model
CN113480093A (en) Double-dosing coupling high-load operation method and system for sewage treatment plant

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication
RJ01 Rejection of invention patent application after publication

Application publication date: 20220426