RU144184U1 - AUTOMATED TRANSPORT MONITORING SYSTEM - Google Patents

Abstract

1. A system for automated monitoring of a traffic stream, comprising at least two registrars, each of which includes at least an information acquisition unit comprising at least one video camera, an information processing and storage unit connected by a communication channel, characterized in that one of the registrars is the main one, others are subordinate, the main registrar contains the information reception and transmission unit inside the system, the decision making unit, the dock forming unit base, connected to the unit for transmitting information to external information receivers and to the archive of the evidence base, while the unit for receiving and transmitting information inside the system of each slave registrar is connected to the unit for receiving and transmitting information inside the system of the main registrar, and the unit for receiving information of each registrar is equipped with forming accurate time. 2. The system according to claim 1, characterized in that the information acquisition unit further comprises a radar broadband unit and / or a traffic light control signal reader. The system according to claim 1, characterized in that the exact time generating means comprises an accurate time signal receiver connected to a constant frequency generation module, which in turn is configured to transmit signals of a certain constant frequency to an information processing and storage unit. The system according to claim 1, characterized in that the information processing and storage unit contains a constant frequency signal assignment module, configured to receive signals from the generation module p�

Description

The utility model relates to road safety systems and is intended for the detection and video recording of traffic violations (traffic rules) by a vehicle (TS), including for the detection and video recording of vehicles that violate the intersection rules, including violations of the rules for changing lanes, pedestrian traffic rules passage, passage to the prohibition signal of traffic light / traffic controller, passage / parking along / in the forbidden lane, as well as to determine the average speed of the vehicle, to control the operation of traffic lights of regulation at the crossroads, to collect statistics on vehicle movement, control of emergency situations on the road sections of any configuration including junctions and w / d travel.

There are various systems and devices for monitoring compliance with traffic rules. But their common drawback is a narrow focus.

So, for example, there is a device for determining the speed and coordinates of vehicles with their subsequent identification and automatic registration of traffic violations (RF patent No. 2382416, IPC G08G 1/052, G08G 1/017, G07C 5/08 (2006.01), publ. 20.02 .2010 Bull. No. 5), containing a radar, a video camera for recording and recognition of state registration plates (GRZ) of vehicles that violate traffic rules, and a control and data processing unit connected to them, a radar containing a signal processing module is used as a radar calculating speeds and and the range of all vehicles located on a selected section of the roadway, and a panoramic video camera has been introduced into the device, providing a survey of a section of the road from 40-50 meters to several hundred meters, which is connected to a control and data processing unit that is equipped with software for synchronizing the operation of the radar and the panoramic video camera, comparing the data streams received from them, obtaining metrologically reliable results of measuring the speeds and coordinates of vehicles that violated the speed the first mode of movement and data transfer for automatic registration of traffic violations, the functions of the camera for panoramic viewing and the functions of the camera for recognizing gas distribution devices can be performed by one wide-angle “megapixel” video camera or several “ordinary” video cameras can be used as video cameras for recording and recognizing gas distribution devices , in accordance with the number of lanes.

Also known is a pedestrian crossing passage control complex (RF patent No. 120270, IPC G08G 1/00 (2006.01), published on 09/10/2012), comprising a video recording unit including at least one video camera and a workstation made with the ability to process data from the radar and video recording unit, while it additionally contains a radar made with the possibility of trajectory measurements for all targets in the control zone and at the same time measuring speed, range, azimuth and dimensions of the target.

There is a comprehensive automated system for monitoring automobile traffic (RF patent No. 76152, IPC G08G 1/00 (2006.01), published September 10, 2008), which contains the following components: vehicle speed measuring device, capable of automatically measuring vehicle speed and transmit vehicle speed data to the hub; license plate recognition complex, configured to automatically recognize the vehicle's GRD and transmit license plate data to the hub; a complex of photo and video recording of traffic violations, made with the possibility of photo and video fixing of the vehicle image, including image fixing with a violation relating to the passage of the vehicle to the traffic signal prohibiting signal and / or its movement in the oncoming lane, as well as with the possibility of transmitting photo- and video images of the vehicle in the hub; a hub configured to: receive data from a vehicle speed measuring device, a license plate recognition complex, and a complex of photo and video recording of traffic violations; the formation of a data set containing data on the vehicle license plate in symbolic form, a set of static images of the vehicle, a video sequence with the vehicle, data on types of traffic violations, data on the vehicle speed, as well as with the possibility of transmitting the said data set to a processing center; a processing center configured to: receive data from a hub; request information about the vehicle and the established speed mode from the specified centralized databases; determining, on the basis of the information received, the situation of an administrative offense; making a decision on the imposition of a penalty; interaction with regional payment systems to control the payment of foreclosed; and interaction with the system of automated printing and distribution of receipts-orders; centralized databases, including aggregate information from databases; a system for the automated printing and distribution of receipts-orders, made with the possibility of printing receipts-orders and their distribution to the owners of the vehicle.

As noted above, the main drawback of these devices is the ability to control only a limited number of types of violations of the MPC - in the first case, a violation of the high-speed mode of movement of the vehicle, in the second case - a violation of the rules for unregulated pedestrian crossings, in the third - violation of the high-speed mode, the vehicle is prohibited traffic light and vehicle traffic in the oncoming lane. However, these devices do not bind the received data to time, which significantly reduces their evidentiary ability. In addition, the above devices and systems are aimed at monitoring direct sections of roads without intersections. Practice shows that it is at the intersections that the greatest number of various violations of the MPC is committed. The installation of several highly specialized systems or devices on one section of the road to ensure control over a wider range of violations of the MPC is extremely economically disadvantageous, since the cost of any of the known systems and devices for monitoring compliance with MPC is very significant.

Also known is the closest to the claimed system of automated monitoring of traffic flow with the function of determining the average speed of the vehicle (RF patent No. 135828, IPC G08G 1/052 (2006.01), publ. 20.12.2013), including at least two registrars, each of which includes at least an information obtaining unit containing at least one video camera, and an information processing and storage unit connected by a communication channel to a remote server, which comprises a unit for calculating the average speed of the vehicle in the area based on the received data about two adjacent registers, time synchronization block among DVRs and comparison unit recognizes license plates from an external database in order to identify and control the movement of transport objects of interest.

The disadvantages of the described system are as follows:

- the lack of linking the data received from the video camera to the time at which each specific frame was taken, in our opinion, this drawback is significant, since the video sequence cannot be an evidence base for violations of the MPC without linking the video frames to the exact time of their shooting, since it can be challenged in court as an insufficient fact of proof of guilt;

- the possibility of joint processing of data from only two neighboring registrars. This condition does not allow the system to be used on branched sections of the road, for example, at intersections, which in turn makes the system narrowly targeted;

- the functional purpose of the system is to determine the average vehicle speed in the area between two neighboring registrars, which does not allow it to be used to provide control over a wide range of traffic violations.

We also note that known receivers of accurate time signals (GLONASS, GPS, etc.) do not allow each frame to be assigned a unique time stamp, since they receive a precise time signal once in a certain period of time (approximately once per second). During this time, the camera makes more than one frame (the frame rate of the video camera is at least 24 frames per second). Accordingly, at least 24 frames will be assigned the same time stamp, which in our opinion is unacceptable.

The technical effects of the proposed system are to synchronize the time and location of the vehicle relative to a pre-formed model of a road section of any geometry, expand the spectrum of traffic violations recorded in automatic mode, increase the efficiency of processing the received information and, as a result, increase the evidentiary ability of the generated evidence base for traffic violations specific TS and objectivity of obtaining information about the traffic situation on road sections of any configuration incl tea junctions and w / d travel.

To achieve these technical effects in the inventive system of automated monitoring of a traffic stream containing at least two registrars, each of which includes at least an information receiving unit containing at least one video camera, an information processing and storage unit connected by a communication channel, according to a utility model one of the registrars is the main one, the others are subordinates, the main registrar contains the information reception and transmission unit connected in series inside the system, a decision-making unit, an evidence base formation unit connected to an information transfer unit to external information receivers and an evidence base archive, while information reception-transmission units within the system of each slave registrar are connected to the information reception-transmission unit inside the main registrar system, and the information receiving unit of each registrar is equipped with a means for generating accurate time, with the best options for implementing the proposed system, the information receiving unit For further comprises a wideband radar and / or reader traffic light control signals; means for generating accurate time includes a receiver of accurate time signals connected in series with a constant frequency generation module, which in turn is configured to transmit signals of a certain constant frequency to an information processing and storage unit; the information processing and storage unit contains a constant frequency signal assignment module configured to receive signals from the constant frequency generation module and with the possibility of assigning constant frequency signals to data streams coming from the information receiving unit; the information processing and storage unit contains a module for analyzing traffic signal signals from a video camera, a license plate recognition module and building a vehicle moving track, a video archive configured to receive data streams from the information receiving unit, and a track identification module associated with the license plate recognition and building module the vehicle’s moving track, and the information storage module in the database, configured to receive information from other modules of the information processing and storage unit and with the ability to transfer data to the block of reception and transmission of information within the system; the information transmitting and receiving unit inside the system comprises a data sequencing module configured to receive information from the information storage module in the database, as well as the video archive, and transmit data to the decision making unit; the decision block contains a module for converting screen coordinates to logical coordinates on a model, which at the same time contains a pre-formed model of a road section, and a module for deciding whether there is an offense, which at the same time contains a graph connected between each other, in turn, a module for converting screen coordinates to the logical coordinates on the model are made with the ability to receive information from the data sequencing module, and the decision-making module on the presence of an offense is made with the possibility eredavat data of the block formation of evidence; the evidence base formation unit contains a module of necessary and sufficient conditions for evidence base formation and the evidence base generation module from the archive, interconnected, in turn, the evidence base generation module from the archive is configured to receive data from the decision block and transfer data to the evidence base archive and to a unit for transmitting information to external information receivers; a unit for transmitting information to external information receivers is configured to exchange information with external information receivers and obtain information from the evidence base archive; the evidence base archive is configured to transmit information to the information transfer unit to external information receivers; the information processing and storage unit further comprises a module for receiving tracks and speeds and a module for determining pedestrians and / or a module for analyzing traffic signals from a reader, configured to receive data streams from the information receiving unit, in turn, a module for receiving tracks and speeds and a module for determining pedestrians are made with the ability to transmit data to the track identification module, and the traffic signal analysis module from the reader, with the ability to transfer data to the information storage module ni in the database; the main recorder further comprises external information receivers.

The inventive system of automated monitoring of traffic flow provides an opportunity, in addition to monitoring traffic conditions, to register a wide range of traffic violations in automatic mode, including vehicle drivers exceeding speed, violation of vehicle location rules on the roadway, violation of pedestrian crossing passage rules, violation of stopping and parking rules, violation of the requirements of road signs and markings of the carriageway, failure to provide an advantage in traffic to vehicle drivers or pedestrians those who have such an advantage, violation of the rules for overtaking, violation of the rules of a U-turn, passage to a forbidding signal of a traffic light or traffic controller, movement through a railway crossing with a closed or closed barrier, prohibiting a signal of a traffic light or a person on duty when moving, stopping or parking the vehicle at a railway crossing, leaving a place for traffic traffic accident, as well as collect statistics on road traffic on road sections of any configuration, including intersections and railway crossings.

The inventive system allows you to configure the automated monitoring system of the traffic flow as a whole in automatic mode, which in turn eliminates the need for time-consuming and lengthy configuration of each individual registrar included in the inventive system. And thereby reduce the influence of the human factor on the reliability of the data received from the system of automated monitoring of traffic flow. The system of automated monitoring of traffic flow is carried out by preliminary forming a model of the road section on which the system will be installed, the generated model is, in turn, the basis for the graph, based on which the claimed system of automated monitoring of traffic flow in automatic mode concludes that there is a violation of traffic rules for a specific vehicle .

At the same time, the introduction of an accurate time generation tool into the automated monitoring system of the traffic flow, consisting of an accurate time signal receiver and a constant frequency generation module, is an essential condition for the system to work by synchronizing the time and location of the vehicle with respect to a pre-formed model of a road section of any geometry, as otherwise In this case, the footage captured by the video camera cannot be processed by the information processing and storage unit, since only unique tags accurate time assigned to video frames, may uniquely interpret a sequence of video frames and make video suitable for subsequent processing in order to monitor the traffic situation and registering the presence of disturbances MVT in the automatic mode, to the same video without shooting time is unproven from a legal point of view. The principle of operation of the exact time generation means is as follows: receive the exact time signals with the help of the exact time signal receiver and transmit them to the constant frequency generation module, which has the ability to generate signals with a certain constant frequency. The frequency of the signals generated by the constant-frequency generation module is set to a value not less than the frame frequency of the used camera from the calculation so that each frame captured by the video camera can be assigned a unique time stamp generated by the constant-frequency generation module. In this case, the constant frequency generation module in its work focuses on the exact time signals received from the receiver of the exact time signals and regularly checks the generation frequency of the sent time stamps sent to it. In the absence of the next exact time signal, the constant frequency generation module continues to generate signals with the frequency set during the previous verification. When implementing the proposed system, the information receiving unit, in addition to the video camera, may also contain other means of obtaining information (for example, a broadband radar unit, a traffic light control signal reader, etc.). If the information receiving unit contains various means of obtaining information, the constant frequency signal assignment module assigns unique time stamps to all data streams that come from the information receiving unit.

Thus, we can conclude that the inventive system of automated monitoring of the traffic flow provides increased objectivity in obtaining information by providing incoming data with accurate time stamps, ensuring synchronization of the time and location of the vehicle relative to a pre-formed model of the road section on which the system is installed, increasing the efficiency of information processing traffic conditions through the use of the graph when making decisions on the presence of traffic violations in the automatic mode and, as a consequence, increase the ability of evidence formed the evidence base on violations of traffic regulations specific vehicle.

The drawings illustrate the proposed system, where in FIG. 1 is a block diagram of a system for automated monitoring of a traffic stream (general view), FIG. 2 is a block diagram of the main registrar of the claimed system.

The automated traffic flow monitoring system contains at least two registrars, in this particular example (Fig. 1) there are four of them, one of the registrars is the main 1, three more are subordinates 2. Each of the registrars 1-2 includes at least a receiving unit information 3, containing at least one video camera 4 (shown in Fig. 2), the information processing and storage unit 5 connected by a communication channel, the main recorder 1 contains sequentially interconnected information reception and transmission unit inside topic 6, decision block 7, the block for the formation of evidence base 8 connected to the block for transmitting information to external information receivers 9 and the archive of the evidence base 10, while the transmit-receive blocks within the system 6 of each slave registrar 2 are connected with the transmit-receive block information inside the system 6 of the main recorder 1, and the information receiving unit 3 of each registrar 1-2 is equipped with a means for generating the exact time 11, in addition, with the best options for implementing the proposed system, the unit Information 3 further comprises a radar broadband unit 12 and / or a traffic light control signal reader 13, an accurate time generating means 11 comprises an accurate time signal receiver 14 connected to a constant frequency generation module 15, which in turn is configured to transmit signals of a certain constant frequency to an information processing and storage unit 5, an information processing and storage unit 5 comprises a constant frequency signal assignment module 16, configured to of the signals from the constant frequency generation module 15 and with the possibility of assigning constant frequency signals to the data streams coming from the information receiving unit 3, the information processing and storage unit 5 contains a module for analyzing traffic signal signals from a video camera 17, a license plate recognition module, and building a vehicle movement track 18 , video archive 19 made with the possibility of receiving data streams from the information receiving unit 3, as well as a track identification module 20 associated with the license plate recognition and construction module the track of the movement of the vehicle 18, and the information storage module in the database 21 is configured to receive information from the modules 17, 18, 20 and 32 of the information processing and storage unit 5 and with the possibility of transmitting data to the information reception and transmission unit inside the system 6 in turn, contains a data sequencing module 22, configured to receive information from the information storage module in the database 21, as well as the video archive 19, and transmit data to the decision block 7. The decision block 7 contains a pre the formation of screen coordinates into logical coordinates on model 23, which at the same time contains a pre-formed model 24 of the road section, and a decision-making module on the existence of an offense 25, which at the same time contains graph 26, interconnected, in turn, a module for converting screen coordinates to logical the coordinates on the model 23 is configured to receive information from the data sequencing module 22, and the decision-making module on the existence of an offense 25 is configured to transmit data to the formatter Bani evidence

The evidence base formation block 8 contains a module of necessary and sufficient conditions for the formation of the evidence base 27 and the evidence base formation module from the archive 28, connected in series, in turn, the evidence base formation module from the archive 28 is configured to receive data from the decision block 7 and transmit data to the archive of the evidence base 10 and to the unit for transmitting information to external information receivers 9. The unit for transmitting information to external information receivers 9 is configured to exchange and with external information receiver 29 and receiving information from the archive database 10. The archive demonstrative evidence 10 is configured to transmit information to the information transmission unit to the external data receivers

In addition, with the best options for implementing the proposed system, the information processing and storage unit 5 further comprises a module for acquiring tracks and speeds 30 and a module for determining pedestrians 31 and / or a module for analyzing traffic signals from the reader 32, configured to receive data streams from the information receiving unit 3, in turn, the module for obtaining tracks and speeds 30 and the module for determining pedestrians 31 are configured to transmit data to the module for identifying tracks 20, and the module for analyzing traffic signals and from the reader 32 - with the ability to transfer data to the module for storing information in the database 21. The main recorder 1 further comprises external information receivers 29.

The number of registrars included in the inventive system of automated monitoring of traffic flow is determined by the geometry of the road section on which the system will be installed and the spectrum of traffic violations that need to be automatically recorded on this section.

As an example, we give a description of the principle of operation of the inventive system of automated monitoring of traffic flow installed at an adjustable T-junction. The system consists of three registrars, one of which is the main registrar 1, the rest are subordinate registrars 2.

Each of the registrars 1-2, which are part of the automated traffic flow monitoring system, receives information about the traffic flow and traffic conditions through its own information receiving unit 3, in this example consisting of a video camera 4 and means for generating accurate time 11. Tool for generating accurate time 11 , consists of a receiver of accurate time signals 14 (in a specific example, a GPS receiver) and a constant frequency generation module 15, which is designed to generate signals with a specific constant frequency (in the specific example, the frequency of the generated signal is set in the value of signals 25 / sec). The means for generating the exact time 11 is necessary because otherwise the video sequence captured by the video camera 4 cannot be fully processed by the information processing and storage unit 5, since only the unique time stamps assigned to the video frames allow us to unambiguously interpret the sequence of video frames and make the video sequence suitable for subsequent processing in order to monitor traffic conditions and register the presence of traffic violations in the automatic mode by the claimed automation system nnogo monitoring traffic flow. The exact time stamps from the constant frequency generation module 15 are transmitted to the constant frequency signal assignment module 16, which in turn assigns unique accurate time stamps to all data streams coming from the information receiving unit 3 (in a specific example, video frames captured by video camera 4). Further, the data provided with timestamps are sent to the traffic signal analysis module from the video camera 17 and the license plate recognition module and the construction of vehicle tracks 18, as well as to the video archive 19. After processing, the data from module 17 are sent to the information storage module in the database 21 The data processed by module 18 are received by module 21 and track identification module 20, after processing on which they also go to the module for storing information in database 21. Module 21 of each recorder 1-2 all collected data are transmitted emits to the data sequencing module 22 of the information transmitting and receiving unit inside the system 6 of each registrar 1-2. In turn, the data transmit-receive units inside the system 6 of the slave registrars 2 are transmitted, and the data transmit-receive unit inside the system 6 of the main registrar 1 receives data streams to the data sequencing module 22. Also, the data transmit-receive unit inside the system 6 of the main registrar 1 receives data streams from video archives 19 processing and storage units of information of 5 registrars 1-2, after which data from the data receiving and transmitting unit inside the system 6 of the main registrar 1 are sent to the decision block 7 of the main r of the register 1 to the module for converting screen coordinates to logical coordinates on model 23, which in turn contains a preformed model 24 of a road section (in a specific example, a T-junction), on which the inventive system for automated monitoring of traffic flow is installed. From the module 23 of the main registrar 1, the data in the form of logical coordinates is sent to the decision-making module on the existence of an offense 25, which in turn contains column 26. In automatic mode, the information analyzed by means of column 26 is transmitted to the evidence-generating module from the archive 28, which simultaneously this receives the data transmitted by the video archive 19 of each registrar 1-2 of the system. At the same time, module 28 receives information from the module of necessary and sufficient conditions for the formation of evidence base 27, which, like module 28, is part of the formation of evidence base 8. After processing all the information received, module 28 automatically generates evidence packages bases on traffic violations for specific vehicles, supplying them with the necessary evidence in the form of frames captured by video cameras of 4 registrars 1-2 with unique timestamps and documents assigned to them, based on the decision taken by the decision-making module on the existence of an offense 25. The generated evidence base packages from module 28 are sent to the information transfer unit to external information receivers 9 of the main registrar 1 and at the same time to the archive of the evidence base 10 of the main registrar 1. Information transfer unit to external information receivers 9 of the main registrar 1 transmits packages of evidence base to external information receivers 29 (in a specific example, a signal processing console about offenses). Also, if a request is received from external information receivers 29 for the need to re-send certain packages of evidence base, the requested information is transmitted to external information receivers 29 from the archive of the evidence base 10 by means of a unit for transmitting information to external information receivers 9. Moreover, inside the registrars 1- 2 all information between the blocks and modules of each of the registrars 1-2 is transmitted via wired communication channels, mainly digital, and between slave registrars 2 and the main reg istrator 1 and between the information transmission unit to the external receivers 9 of the main information recorder 1 and the external information receiver 29, information is transmitted via 2G / 3G / 4G / wired communication, in a specific example - through 3G wireless communications.

Claims (12)

1. A system for automated monitoring of a traffic stream, comprising at least two registrars, each of which includes at least an information acquisition unit comprising at least one video camera, an information processing and storage unit connected by a communication channel, characterized in that one of the registrars is the main one, others are subordinate, the main registrar contains the information reception and transmission unit inside the system, the decision making unit, the dock forming unit base, connected to the unit for transmitting information to external information receivers and to the archive of the evidence base, while the unit for receiving and transmitting information inside the system of each slave registrar is connected to the unit for receiving and transmitting information inside the system of the main registrar, and the unit for receiving information of each registrar is equipped with forming accurate time. 2. The system according to claim 1, characterized in that the information acquisition unit further comprises a radar broadband unit and / or a traffic light control signal reader. 3. The system according to claim 1, characterized in that the exact time generating means comprises an accurate time signal receiver connected to a constant frequency generation module, which in turn is configured to transmit signals of a certain constant frequency to an information processing and storage unit. 4. The system according to claim 1, characterized in that the information processing and storage unit comprises a constant frequency signal assignment module, configured to receive signals from the constant frequency generation module and with the possibility of assigning constant frequency signals to data streams coming from the information receiving unit. 5. The system according to claim 1, characterized in that the information processing and storage unit comprises a module for analyzing traffic signals from a video camera, a license plate recognition module and constructing a vehicle moving track, a video archive configured to receive data streams from the information receiving unit, and also a module for identifying tracks associated with a module for recognizing license plates and building a track for moving a vehicle, and a module for storing information in a database, configured to radiation information from other modules of the information processing and storage unit, and to transmit data to the reception and transmission of information within the system. 6. The system according to claim 1, characterized in that the information transmitting and receiving unit inside the system contains a data sequencing module, configured to receive information from the information storage module in the database, as well as the video archive, and transmit data to the decision unit. 7. The system according to claim 1, characterized in that the decision-making unit contains a module for converting screen coordinates into logical coordinates on a model, which at the same time contains a pre-formed model of a road section and a decision-making module on the presence of an offense, which in this case contains a graph related to between themselves, in turn, the module for converting screen coordinates to logical coordinates on the model is configured to receive information from the data ordering module, and the decision-making module on the availability of right onarusheniya adapted to transmit data to the forming unit evidence. 8. The system under item 1, characterized in that the evidence base formation unit contains a module of necessary and sufficient conditions for evidence base formation and the evidence base formation module from the archive, interconnected, in turn, the evidence base formation module from the archive is configured to accept data from the decision making unit and transferring data to the evidence base archive and to the information transfer unit to external information receivers. 9. The system according to claim 1, characterized in that the unit for transmitting information to external information receivers is configured to exchange information with external information receivers and obtain information from the archive of the evidence base. 10. The system according to claim 1, characterized in that the evidence base archive is configured to transmit information to the information transfer unit to external information receivers. 11. The system according to claim 1, characterized in that the information processing and storage unit further comprises a module for receiving tracks and speeds and a module for determining pedestrians and / or a module for analyzing traffic signals from a reader, configured to receive data streams from the information receiving unit, in turn, the module for obtaining tracks and speeds and the module for determining pedestrians are configured to transmit data to the module for identifying tracks, and the module for analyzing traffic signals from the reader is capable of transmitting data to the module for storing information in the database. 12. The system according to claim 1, characterized in that the main recorder further comprises external information receivers.