Gas pipeline network monitoring point layout method based on improved greedy algorithm

Abstract

The application relates to a gas pipe network monitoring point layout method based on an improved greedy algorithm, and belongs to the technical field of gas pipe network monitoring. The method solves the problems of unreasonable monitoring point distribution and low artificial inspection efficiency in the prior art. The layout method comprises the following steps: performing discretization processing on a gas pipe network to obtain a corresponding total set of gas pipeline discrete points; updating the total set of gas pipeline discrete points and a candidate sensor point set according to original sensor layout points; updating the total set of gas pipeline discrete points and the candidate sensor point set according to a point set of a key protection area; based on the improved greedy algorithm, sequentially selecting one point from the candidate sensor point set as a layout point of a non-key protection area sensor, until all the sensors to be laid are laid, and obtaining the layout point of the non-key protection area sensor. The method realizes reasonable distribution of monitoring points and automatic monitoring of the gas pipe network.

Description

Technical Field

[0001] This invention relates to the field of gas pipeline network monitoring technology, and in particular to a method for deploying gas pipeline network monitoring points based on an improved greedy algorithm. Background Technology

[0002] The safe operation of urban gas is crucial to the lives and safety of tens of millions of urban residents and is a vital guarantee for urban life and social development. In the new era, the continuous increase in urban gas consumption has greatly promoted the development of urban gas companies and led to the sustained growth of urban gas pipelines, bringing convenience to more and more urban residents. However, the probability of gas pipeline safety accidents is also constantly increasing. Because gas leaks often occur suddenly, if the leaked gas is not promptly vented, it can easily cause serious safety accidents such as fires and explosions. Urban gas pipelines are often distributed in densely populated areas; therefore, once a gas leak occurs, it will threaten urban public safety and, in severe cases, cause casualties and property damage. Timely measures must be taken to control the situation and minimize the loss of life and property caused by gas leaks.

[0003] In response to the frequent gas leaks and explosions, timely and effective monitoring of the real-time status of urban gas pipeline networks, and rapid and accurate detection and timely handling of gas leaks within and even underground pipelines, is of paramount importance for ensuring gas safety. Current gas leak monitoring systems face several challenges:

[0004] 1. Currently, gas operators mostly rely on manual inspections for gas pipeline leak monitoring. This method requires companies to dispatch inspectors who use handheld combustible gas monitoring terminals or mobile monitoring vehicles to detect leaks. The frequency of manual monitoring depends heavily on the inspection cycle, making it impossible to monitor large-scale gas pipeline leaks within a city 24 hours a day. Its timeliness and effectiveness are poor, and it is also highly dependent on the qualifications and sense of responsibility of the inspectors.

[0005] 2. Pressure monitoring, a common method for gas leak detection, involves installing pressure gauges on gas pipelines to monitor pressure and flow at various points along the pipeline in real time. When a gas leak occurs, the pressure in the pipeline changes. However, pressure sensor installation and daily maintenance are costly and complex, making it difficult to achieve large-scale, dense deployment in urban areas in the short term, thus limiting the coverage of leak detection.

[0006] 3. In the current application scenarios of gas leak monitoring, monitoring points are mainly selected based on the results of risk identification, such as pipelines with poor health, high risk, long service life, gas pipelines and rainwater and sewage pipelines that intersect with gas pipelines, and power line inspection wells. However, monitoring points are often distributed unevenly based on risk level, and some areas have too few sensors, which may lead to the inability to detect gas leaks in time, or even gas explosions.

[0007] Therefore, there is an urgent need for a technical solution for comprehensive automatic monitoring of gas pipeline networks. Summary of the Invention

[0008] Based on the above analysis, the present invention aims to provide a method for deploying gas pipeline monitoring points based on an improved greedy algorithm, in order to solve the problems of uneven distribution of monitoring points and low efficiency of manual inspection in the prior art.

[0009] This invention provides a method for deploying gas pipeline monitoring points based on an improved greedy algorithm. The deployment method includes:

[0010] Discretize the gas pipeline network to obtain the total set of discrete points of the corresponding gas pipelines; set the total number of sensors to be deployed.

[0011] Determine suitable locations for sensor placement to obtain a candidate sensor location set; determine the coverage discrete points corresponding to the original sensor locations based on the original sensor locations and sensor monitoring radii; update the total set of discrete points for the gas pipeline based on the coverage discrete points corresponding to the original sensor locations; and update the candidate sensor location set based on the original sensor locations.

[0012] Based on the set of points in the key protection area, the set of candidate sensor points, and the sensor monitoring radius, the deployment points of sensors in the key protection area and the corresponding discrete coverage points of the sensor deployment points in the key protection area are determined; the total set of discrete points of the gas pipeline is updated based on the discrete coverage points of the sensor deployment points in the key protection area; and the set of candidate sensor points is updated based on the deployment points of the sensors in the key protection area.

[0013] Based on the improved greedy algorithm, one point is selected from the candidate sensor point set as a deployment point for the sensor in the non-key protection area, until all the sensors to be deployed are deployed, thus obtaining the deployment points of the sensors in the non-key protection area.

[0014] Based on a further improvement to the above method, the step of sequentially selecting a point from the candidate sensor location set as a deployment point for a sensor in a non-critical protection area, until all sensors to be deployed have been completed, includes:

[0015] Step S41: Determine the coverage discrete point corresponding to each candidate point in the candidate sensor point set, and take the candidate point with the most corresponding coverage discrete points as a deployment point of the sensor in the non-key protection area of ​​the current iteration.

[0016] Step S42: Update the candidate sensor location set according to the deployment locations of sensors in the non-key protection areas of the current iteration; update the total set of discrete points of the gas pipeline according to the coverage discrete points corresponding to the deployment locations of sensors in the non-key protection areas of the current iteration.

[0017] Step S43: Determine whether the sensors to be deployed have been deployed. If not, return to step S41 for the next iteration. If the deployment is complete, end the loop.

[0018] Based on a further improvement to the above method, determining the coverage discrete point corresponding to each candidate sensor point in the candidate sensor point set includes:

[0019] Using the location of each candidate sensor point in the candidate sensor point set as the center, and a multiple of the sensor monitoring radius as the radius, a circular coverage area for each candidate point is obtained; the range of a is [0.75-1.25].

[0020] The discrete points covered by the circular coverage area of ​​each candidate point are taken as the corresponding coverage discrete points of each candidate point.

[0021] Based on a further improvement of the above method, updating the candidate sensor location set according to the deployment locations of sensors in the non-key protection areas of the current iteration includes: deleting the deployment locations of sensors in the non-key protection areas of the current iteration from the candidate sensor location set.

[0022] The step of updating the total set of discrete points for gas pipelines based on the coverage discrete points corresponding to the deployment points of sensors in non-key protection areas in the current iteration includes: deleting the coverage discrete points corresponding to the deployment points of sensors in non-key protection areas in the current iteration from the total set of discrete points for gas pipelines.

[0023] Based on a further improvement to the above method, the discretization of the gas pipeline network to obtain the total set of discrete points of the corresponding gas pipelines includes:

[0024] For each pipeline segment in the gas pipeline network, when the length of the pipeline segment is less than or equal to the preset length, the two pipe points of the pipeline segment are taken as the discrete points corresponding to the pipeline segment.

[0025] When the length of the pipeline segment is greater than the preset length, starting from any one of the two pipe points of the pipeline segment, a new discrete point is obtained every preset length. All the new discrete points of the pipeline segment and the two pipe points of the pipeline segment are used as the discrete points corresponding to the pipeline segment.

[0026] The discrete points corresponding to all pipeline segments in the gas pipeline network are taken as the total set of discrete points of the gas pipeline.

[0027] Based on a further improvement to the above method, the step of determining the deployment locations of sensors in the key protection area and the corresponding discrete coverage points based on the set of locations in the key protection area, the set of candidate sensor locations, and the sensor monitoring radius includes:

[0028] Step S31: Select a regional point from the set of points in the key protection area, determine the distance between the regional point and each candidate point in the set of candidate sensor points, and obtain the shortest distance corresponding to the regional point in the current iteration;

[0029] Step S32: If the shortest distance is less than or equal to the sensor detection radius, the candidate point corresponding to the shortest distance is used as the deployment point of the sensor in the key protection area, and the coverage discrete point corresponding to the deployment point is determined.

[0030] Step S33: Delete the aforementioned regional points from the point set of the key protection area in the current iteration; update the candidate sensor point set according to the deployment points of the sensors in the key protection area, and update the total set of discrete points of the gas pipeline according to the coverage discrete points corresponding to the deployment points;

[0031] Step S34: Determine whether there are still location points in the set of locations in the key protection area. If there are still location points, return to step S31 for the next iteration until there are no location points in the set of locations in the key protection area.

[0032] Based on a further improvement of the above method, determining the coverage discrete point corresponding to the deployment point includes:

[0033] Using the location of the deployment point as the center and the sensor monitoring radius as the radius, a circular coverage area of ​​the deployment point is obtained. The discrete points covered by the circular coverage area of ​​the deployment point are taken as the corresponding discrete coverage points of the deployment point.

[0034] Based on a further improvement of the above method, updating the candidate sensor point set according to the deployment points of the sensors in the key protection area includes: deleting the deployment points in the candidate sensor point set.

[0035] The step of updating the total set of discrete points of gas pipelines based on the coverage discrete points corresponding to the deployment points includes: deleting the coverage discrete points corresponding to the deployment points from the total set of discrete points of gas pipelines.

[0036] Based on a further improvement of the above method, the step of updating the total set of discrete points of the gas pipeline according to the coverage discrete points corresponding to the original sensor points includes: deleting the coverage discrete points corresponding to the original sensor points in the total set of discrete points of the gas pipeline.

[0037] The step of updating the candidate sensor point set based on the original sensor points includes: deleting the original sensor points from the candidate sensor point set.

[0038] Based on a further improvement of the above method, the deployment method further includes:

[0039] Once all the sensors to be deployed have been deployed, the total number of discrete coverage points is determined based on the coverage discrete points corresponding to the original sensor deployment points, the coverage discrete points corresponding to the sensor deployment points in key protection areas, and the coverage discrete points corresponding to the sensor deployment points in non-key protection areas.

[0040] The monitoring coverage rate at the end of the deployment is determined based on the total number of discrete points covered and the total number of discrete points in the total set of discrete points for gas pipelines.

[0041] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0042] 1. This invention discretizes the gas pipeline network, updates the total set of discrete points and the set of candidate sensor points based on the original sensor locations and the set of points in key protection areas, and deploys all the sensors to be deployed based on an improved greedy algorithm, thereby achieving a reasonable distribution of monitoring points and automated monitoring of the gas pipeline network.

[0043] 2. This invention adjusts the circular coverage area of ​​candidate points by adjusting the distribution density of sensors deployed in the gas pipeline network, thereby controlling the density of sensor distribution.

[0044] 3. By setting the sensor as a concentration sensor, this invention can effectively solve the technical problems of low effective data acquisition efficiency, high economic cost, and small effective monitoring range of the pressure monitoring method, and realize low-cost and wide-range detection of gas pipeline networks.

[0045] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0046] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0047] Figure 1 This is a flowchart illustrating the gas pipeline monitoring point deployment method based on an improved greedy algorithm provided in an embodiment of the present invention.

[0048] Figure 2 A schematic diagram showing the distribution of the gas pipeline network before discretization, provided in an embodiment of the present invention;

[0049] Figure 3 A schematic diagram illustrating the distribution of the discretized gas pipeline network provided in an embodiment of the present invention;

[0050] Figure 4 A flowchart illustrating step S3 of the gas pipeline network monitoring point deployment method based on an improved greedy algorithm provided in an embodiment of the present invention;

[0051] Figure 5 This is a flowchart illustrating step S4 of the gas pipeline network monitoring point deployment method based on an improved greedy algorithm provided in an embodiment of the present invention. Detailed Implementation

[0052] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0053] A specific embodiment of the present invention discloses a method for deploying gas pipeline monitoring points based on an improved greedy algorithm, such as... Figure 1 As shown, the deployment method includes:

[0054] Step S1: Discretize the gas pipeline network to obtain the total set of discrete points of the corresponding gas pipelines; set the total number of sensors to be deployed.

[0055] Step S2: Determine the locations where sensors can be placed to obtain a set of candidate sensor locations; determine the coverage discrete points corresponding to the original sensor locations based on the original sensor locations and sensor monitoring radii; update the total set of discrete points for the gas pipeline based on the coverage discrete points corresponding to the original sensor locations; and update the set of candidate sensor locations based on the original sensor locations.

[0056] Step S3: Based on the set of points in the key protection area, the set of candidate sensor points, and the sensor monitoring radius, determine the deployment points of sensors in the key protection area and the corresponding discrete coverage points of the sensor deployment points in the key protection area; update the total set of discrete points of the gas pipeline based on the discrete coverage points of the sensor deployment points in the key protection area; and update the set of candidate sensor points based on the deployment points of sensors in the key protection area.

[0057] Step S4: Based on the improved greedy algorithm, select one point from the candidate sensor point set as a deployment point for the sensor in the non-key protection area, until all the sensors to be deployed are deployed, and obtain the deployment points of the sensors in the non-key protection area.

[0058] Specifically, such as Figure 2 As shown, based on the distribution of the gas pipeline network, it can be seen that there are multiple pipeline segments within the network, which are interconnected to form the gas pipeline network. The endpoint where two pipeline segments connect is called a pipe point, which can be a manhole for the gas pipeline network. Manholes can be used to place sensors to detect gas leaks within the sensor's detection radius.

[0059] Specifically, existing sensor locations are those where sensors are already placed, while candidate sensor locations are potential locations for sensor placement, including existing sensor locations. Within the gas pipeline network, there are key protection zones. The center point of these key protection zones is designated as the sensor locations. Key protection zones include areas such as schools, chemical plants, and industrial parks. According to relevant national regulations, monitoring and sensor deployment should prioritize these key protection zones within the gas pipeline network.

[0060] Specifically, in Figure 2 In the diagram, B1, B2, and B3 are the original sensor locations, A1, A2, A3, A4, A5, and A6, as well as B1, B2, and B3 are candidate sensor locations, and C1 and C2 are locations in the key protection area.

[0061] Specifically, in step S1, the gas pipeline network is discretized to obtain the total set of discrete points of the corresponding gas pipelines, such as... Figure 3 As shown.

[0062] Preferably, the discretization of the gas pipeline network to obtain the total set of discrete points of the corresponding gas pipelines includes:

[0063] For each pipeline segment in the gas pipeline network, when the length of the pipeline segment is less than or equal to the preset length, the two pipe points of the pipeline segment are taken as the discrete points corresponding to the pipeline segment.

[0064] When the length of the pipeline segment is greater than the preset length, starting from any one of the two pipe points of the pipeline segment, a new discrete point is obtained every preset length. All the new discrete points of the pipeline segment and the two pipe points of the pipeline segment are used as the discrete points corresponding to the pipeline segment.

[0065] The discrete points corresponding to all pipeline segments in the gas pipeline network are taken as the total set of discrete points of the gas pipeline.

[0066] Specifically, such as Figure 3 As shown, each pipeline segment in the gas pipeline network has a different length. The pipeline segments are divided according to their length. When the length of a pipeline segment is less than or equal to a preset length, the two points on that segment are taken as discrete points. The preset length can be set within the range of 1 to 5 meters. The smaller the preset length, the more discrete points are generated, requiring more data calculations during processing, but resulting in more accurate monitoring coverage. Conversely, the larger the preset length, the fewer discrete points are generated, requiring less data calculations, but resulting in greater errors in the obtained monitoring coverage. Therefore, it is worth noting that the specific value of the preset length needs to be set reasonably based on the computing resources of the processing equipment, which will not be elaborated further here.

[0067] In the set of discrete points of the gas pipeline, each discrete point is assigned a discrete point number and discrete point location information, which are the geographical coordinates of the discrete point's location.

[0068] It is worth noting that the total number of discrete points included in the set of discrete points of the gas pipeline in step S1 is the total number of discrete points of the entire gas pipeline network.

[0069] Specifically, in step S1, the total number of sensors to be deployed is set. The sensors to be deployed are new sensors added to the existing sensors. Since the placement of the new sensors is unknown, the present invention needs to automatically determine the location of the new sensors and combine the new sensors with the existing sensors to maximize the monitoring coverage of the gas pipeline network.

[0070] It is understandable that, for a gas pipeline network, the monitoring coverage rate of each gas pipeline network = the coverage of all discrete points of all sensors deployed in the gas pipeline network / the total number of discrete points in the gas pipeline network * 100%.

[0071] Specifically, the sensor monitoring radius of the new sensor to be deployed can be set to be the same as or different from that of the existing sensors. This can be configured based on the specific performance characteristics of each sensor.

[0072] The sensor to be deployed in this embodiment of the invention is preferably a concentration sensor. The concentration sensor can periodically collect the concentration of combustible gas. When the concentration of gas in the air exceeds the set value, an alarm will be triggered. Moreover, since the concentration sensor is inexpensive, it can be used for large-scale urban gas pipeline network leak monitoring, helping gas operators to detect pipeline leaks in a timely and accurate manner, providing data and technical support for subsequent incident handling, and quickly and effectively handling emergencies.

[0073] Specifically, in step S2, by collecting data from different gas pipeline networks, the existing sensor locations and potential sensor locations within those networks are determined, and both are included in the candidate sensor location set. For example... Figure 3 Points A1, A2, A3, A4, A5, and A6, as well as B1, B2, and B3.

[0074] Specifically, the coverage discrete points corresponding to the original sensor deployment locations are determined based on the original sensor locations and their monitoring radii. Various monitoring parameters of the original sensors can be determined by collecting historical monitoring data from the gas pipeline network or by using historical installation parameters; these will not be elaborated upon here. Figure 3 As shown, taking the original sensor B2 as an example, the monitoring coverage area of ​​sensor B2 is a circular area with a radius of R. The corresponding discrete points of sensor B2 are the discrete points covered by the circular area with a radius of R and the position of sensor B2 as the circle.

[0075] After determining the locations of the existing sensors and their corresponding discrete coverage points, the candidate sensor location set is updated based on the locations of the existing sensors, including deleting the locations of the existing sensors from the candidate sensor location set; the gas pipeline discrete point set is updated based on the discrete coverage points corresponding to the locations of the existing sensors, including deleting the discrete coverage points corresponding to the locations of the existing sensors from the total set of gas pipeline discrete points.

[0076] It is worth noting that after step S2 is completed, the total set of discrete points for the gas pipeline no longer includes the discrete points covered by the original sensor locations, and the set of candidate sensor locations no longer includes the original sensor locations. That is, the candidate sensor locations only include locations A1, A2, A3, A4, A5, and A6.

[0077] Specifically, in step S3, based on the set of points in the key protection area, the set of candidate sensor points, and the sensor monitoring radius, the deployment points of the sensors in the key protection area and the corresponding discrete coverage points are determined; the total set of discrete points of the gas pipeline is updated based on the discrete coverage points corresponding to the deployment points of the sensors in the key protection area; and the set of candidate sensor points is updated based on the deployment points of the sensors in the key protection area.

[0078] Specifically, such as Figure 3 As shown, the key protection area includes points C1 and C2, and the candidate sensor point set includes points A1, A2, A3, A4, A5 and A6. The sensor monitoring radius is determined according to the parameters of the sensor to be set, and the sensor monitoring radius r is generally around 500m.

[0079] Preferably, such as Figure 4 As shown, the step of determining the deployment locations of sensors in the key protection area and the corresponding discrete coverage points based on the set of locations in the key protection area, the set of candidate sensor locations, and the sensor monitoring radius includes:

[0080] Step S31: Select a regional point from the set of points in the key protection area, determine the distance between the regional point and each candidate point in the set of candidate sensor points, and obtain the shortest distance corresponding to the regional point in the current iteration;

[0081] Step S32: If the shortest distance is less than or equal to the sensor detection radius, the candidate point corresponding to the shortest distance is used as the deployment point of the sensor in the key protection area, and the coverage discrete point corresponding to the deployment point is determined.

[0082] Step S33: Delete the aforementioned regional points from the point set of the key protection area in the current iteration; update the candidate sensor point set according to the deployment points of the sensors in the key protection area, and update the total set of discrete points of the gas pipeline according to the coverage discrete points corresponding to the deployment points;

[0083] Step S34: Determine whether there are still location points in the set of locations in the key protection area. If there are still location points, return to step S31 for the next iteration until there are no location points in the set of locations in the key protection area.

[0084] Specifically, such as Figure 3 As shown, the set of points in the key protection area includes point C1 and point C2. Point C1 and point C2 represent the location of the center point of the key protection area. Here, point C2 is taken as an example.

[0085] Specifically, in step S31, point C2 is selected from the set of points in the key protection area. The candidate sensor point set includes points A1, A2, A3, A4, A5, and A6. The distances between the area point C2 and the candidate points A1, A2, A3, A4, A5, and A6 are calculated and represented as C2A1, C2A2, C2A3, C2A4, C2A5, and C2A6, respectively. By comparing the values ​​of C2A1, C2A2, C2A3, C2A4, C2A5, and C2A6, a shortest distance can be determined as the shortest distance corresponding to the area point in the current iteration. Figure 3 The gas pipeline network provided in the data shows that the shortest distance corresponding to location C2 in the area is C2A3.

[0086] Specifically, in step S32, the shortest distance C2A3 is compared with the sensor detection radius r of the sensor to be deployed. If the shortest distance C2A3 is less than or equal to the sensor detection radius r, then the candidate point A3 corresponding to the shortest distance C2A3 is taken as the deployment point of the sensor in the key protection area, and the coverage discrete point corresponding to the deployment point is determined.

[0087] After step S32 is completed, taking the example where the shortest distance C2A3 is less than the sensor detection radius r, point A3 is designated as the deployment point for sensors in key protection areas. These sensors are specifically designed for monitoring key protection areas. The corresponding discrete coverage points are then determined based on point A3.

[0088] Preferably, determining the coverage discrete point corresponding to the deployment point includes:

[0089] Using the location of the deployment point as the center and the sensor monitoring radius as the radius, a circular coverage area of ​​the deployment point is obtained. The discrete points covered by the circular coverage area of ​​the deployment point are taken as the corresponding discrete coverage points of the deployment point.

[0090] Specifically, taking the location of deployment point A3 as a circle and the sensor monitoring radius r as the radius, the circular coverage area of ​​deployment point A3 can be obtained. The discrete points covered by the circular coverage area of ​​deployment point A3 are taken as the corresponding discrete coverage points of deployment point A3.

[0091] Specifically, in step S33, the current iteration's regional point is deleted from the point set of the key protection area, that is, the current iteration's regional point C2 is deleted from the set composed of point C1 and point C2, so that only point C1 remains in the point set of the key protection area.

[0092] In this embodiment of the invention, step S33 updates the total set of discrete points of the gas pipeline. The total set of discrete points of the gas pipeline before the update is the total set of discrete points of the gas pipeline obtained after step S2 is executed in this embodiment of the invention. In this embodiment of the invention, step S33 updates the set of candidate sensor locations. The set of candidate sensor locations before the update is the set of candidate sensor locations obtained after step S2 is executed in this embodiment of the invention.

[0093] Preferably, updating the candidate sensor location set based on the deployment locations of sensors in the key protection area includes: deleting the deployment locations from the candidate sensor location set;

[0094] The step of updating the total set of discrete points of gas pipelines based on the coverage discrete points corresponding to the deployment points includes: deleting the coverage discrete points corresponding to the deployment points from the total set of discrete points of gas pipelines.

[0095] Specifically, the sensor deployment point in the key protection area is point A3, and the candidate sensor point set is points A1, A2, A3, A4, A5 and A6. Point A3 is deleted from points A1, A2, A3, A4, A5 and A6, and points A1, A2, A4, A5 and A6 are used as the updated candidate sensor point set.

[0096] Specifically, in step S34, it is determined whether there are still regional points in the set of points in the key protection area. If regional point C1 still exists, the process returns to step S31 for the next iteration. In the next iteration, regional point C1 is used to determine the distance between regional point C1 and the candidate sensor point sets A1, A2, A4, A5, and A6. The shortest distance between C1A1, C1A2, C1A4, C1A5, and C1A6 is C1A1, thus determining the coverage discrete point of point A1. After step S33, if there are no regional points in the set of points in the key protection area, the process returns to step S4.

[0097] Specifically, in step S4, based on the improved greedy algorithm, one point is selected from the candidate sensor point set as a deployment point for the sensor in the non-key protection area, until all the sensors to be deployed are deployed, and the deployment points of the sensors in the non-key protection area are obtained.

[0098] At this point, after step S3 is completed, assuming that there are still candidate sensor locations A1, A2, A4, A5 and A6 remaining, and there are still 3 sensors to be deployed, then 3 candidate locations need to be selected from the candidate sensor location set as the deployment locations of the sensors to be deployed.

[0099] Understandably, greedy algorithms generally proceed with the following steps:

[0100] ① Establish a mathematical model to describe the problem;

[0101] ② Divide the problem into several sub-problems;

[0102] ③ Solve each subproblem to obtain the local optimal solution to the subproblem;

[0103] ④ Combine the locally optimal solutions of the subproblems into a single solution to the original problem.

[0104] Greedy algorithms are a simpler and faster design technique for certain optimal solutions to problems. The characteristic of greedy algorithms is that they proceed step-by-step, making the optimal choice based on a certain optimization metric within the current situation, without considering all possible overall scenarios. This saves a significant amount of time that would otherwise be spent exhaustively searching for the optimal solution. Greedy algorithms use a top-down, iterative approach, making successive greedy choices. Each greedy choice simplifies the problem into a smaller subproblem, and through each step, an optimal solution can be obtained. Although each step aims to achieve a local optimum, the resulting global solution may not always be optimal; therefore, greedy algorithms should not backtrack.

[0105] Specifically, in step S4, by improving the greedy algorithm, a deployment point is selected from the candidate sensor point set points A1, A2, A4, A5 and A6 in sequence until all three sensors are deployed, thereby obtaining the deployment points of the three non-key protection area sensors.

[0106] Preferably, such as Figure 5 As shown, the step of sequentially selecting a point from the candidate sensor location set as a deployment point for a sensor in a non-critical protection area, until all sensors to be deployed are completed, includes:

[0107] Step S41: Determine the coverage discrete point corresponding to each candidate point in the candidate sensor point set, and take the candidate point with the most corresponding coverage discrete points as a deployment point of the sensor in the non-key protection area of ​​the current iteration.

[0108] Step S42: Update the candidate sensor location set according to the deployment locations of sensors in the non-key protection areas of the current iteration; update the total set of discrete points of the gas pipeline according to the coverage discrete points corresponding to the deployment locations of sensors in the non-key protection areas of the current iteration.

[0109] Step S43: Determine whether the sensors to be deployed have been deployed. If not, return to step S41 for the next iteration. If the deployment is complete, end the loop.

[0110] Specifically, in step S4, according to Figure 3 After step S3 is completed, there are still 3 sensors that need to be deployed in the provided gas pipeline network. Therefore, steps S41, S42 and S43 need to be executed 3 times, and a deployment point is selected in each execution.

[0111] Specifically, in step S41, the discrete coverage points corresponding to each candidate sensor location in the candidate sensor location sets A1, A2, A4, A5, and A6 are determined and denoted as A1', A2', A4', A5', and A6'. A1', A2', A4', A5', and A6' are compared, and the candidate location with the most corresponding discrete coverage points is selected as a deployment point for the non-key protection area sensor in the current iteration. It can be understood that the discrete points in A1', A2', A4', A5', and A6' are all discrete points in the total set of discrete gas pipeline points after step S3 has been completed.

[0112] Preferably, determining the coverage discrete point corresponding to each candidate sensor point in the candidate sensor point set includes:

[0113] Using the location of each candidate sensor point in the candidate sensor point set as the center, and a multiple of the sensor monitoring radius as the radius, a circular coverage area for each candidate point is obtained; the range of a is [0.75-1.25].

[0114] The discrete points covered by the circular coverage area of ​​each candidate point are taken as the corresponding coverage discrete points of each candidate point.

[0115] Specifically, with candidate points A1, A2, A4, A5, and A6 as centers and a times the sensor monitoring radius r as the radius, a circular coverage area is obtained for each candidate point. The discrete points covered by the circular coverage area of ​​each candidate point are taken as the corresponding discrete coverage points for each candidate point.

[0116] Preferably, the range of 'a' is [0.75-1.25]. It is important to emphasize that after all the sensors to be deployed have been installed, the range of 'a' can be adjusted according to the distribution of the sensors. For example, if the user believes the sensors to be deployed are densely distributed, 'a' can be increased to make the distribution of the sensors sparser; if the user believes the sensors to be deployed are sparsely distributed, 'a' can be decreased to make the distribution of the sensors denser. Generally, 'a' is set to 1.

[0117] Preferably, updating the candidate sensor location set based on the deployment locations of sensors in the non-key protection areas of the current iteration includes: deleting the deployment locations of sensors in the non-key protection areas of the current iteration from the candidate sensor location set;

[0118] The step of updating the total set of discrete points for gas pipelines based on the coverage discrete points corresponding to the deployment points of sensors in non-key protection areas in the current iteration includes: deleting the coverage discrete points corresponding to the deployment points of sensors in non-key protection areas in the current iteration from the total set of discrete points for gas pipelines.

[0119] Specifically, in step S4, during each iteration, a deployment point for the sensor in the non-key protection area of ​​the current iteration can be determined according to step S41. In step S42, the deployment point for the sensor in the non-key protection area of ​​the current iteration is deleted from the candidate sensor point set, and the coverage discrete point corresponding to the deployment point for the sensor in the non-key protection area of ​​the current iteration is deleted from the total set of discrete points of the gas pipeline.

[0120] After step S4 is completed, all the sensors to be deployed will be deployed. At this time, the deployment points of the sensors in the key protection area and the deployment points of the sensors in the non-key protection area are the deployment points of the sensors to be deployed.

[0121] Preferably, the deployment method further includes:

[0122] Once all the sensors to be deployed have been deployed, the total number of discrete coverage points is determined based on the coverage discrete points corresponding to the original sensor deployment points, the coverage discrete points corresponding to the sensor deployment points in key protection areas, and the coverage discrete points corresponding to the sensor deployment points in non-key protection areas.

[0123] The monitoring coverage rate at the end of the deployment is determined based on the total number of discrete points covered and the total number of discrete points in the total set of discrete points for gas pipelines.

[0124] Specifically, after step S4 is completed, all the sensors to be deployed will be deployed. At this point, the total number of discrete points of the gas pipeline network is the sum of the coverage discrete points corresponding to the original sensor deployment points, the coverage discrete points corresponding to the sensor deployment points in key protection areas, and the coverage discrete points corresponding to the sensor deployment points in non-key protection areas.

[0125] At the same time, by combining the total number of discrete points in the total set of discrete points of the gas pipeline after discretization in step S1 of the gas pipeline network and the total number of discrete points of the gas pipeline network coverage, the monitoring coverage rate when the gas pipeline network is completed can be determined, that is, the detection coverage rate of the gas pipeline network = the total number of discrete points of the gas pipeline network coverage / the total number of discrete points in the total set of discrete points of the gas pipeline.

[0126] Compared with existing technologies, the gas pipeline monitoring point deployment method based on an improved greedy algorithm provided in this invention discretizes the gas pipeline network. It updates the total set of discrete points and the candidate sensor set based on the existing sensor locations and the set of points in key protection areas. Using the improved greedy algorithm, it deploys all the required number of sensors, achieving a reasonable distribution of monitoring points and automated monitoring of the gas pipeline network. Furthermore, by adjusting the circular coverage area of ​​the candidate points based on the sensor distribution density within the gas pipeline network, the density of sensor distribution can be controlled. Simultaneously, by setting the sensors as concentration sensors, it effectively solves the technical problems of low effective data acquisition efficiency, high economic cost, and small effective monitoring range associated with pressure monitoring methods, achieving low-cost and wide-range detection of the gas pipeline network.

[0127] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware, and the program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0128] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for deploying monitoring points in a gas pipeline network based on an improved greedy algorithm, characterized in that, The deployment method includes: Discretize the gas pipeline network to obtain the total set of discrete points of the corresponding gas pipelines; set the total number of sensors to be deployed. The process involves: identifying suitable sensor locations to obtain a candidate sensor location set; determining the coverage discrete points corresponding to the existing sensor locations based on their locations and monitoring radii; updating the overall set of discrete points for the gas pipeline based on the coverage discrete points corresponding to the existing sensor locations, including deleting the coverage discrete points corresponding to the existing sensor locations from the overall set of discrete points for the gas pipeline; and updating the candidate sensor location set based on the existing sensor locations, including deleting the existing sensor locations from the candidate sensor location set. Based on the set of points in the key protection area, the set of candidate sensor points, and the sensor monitoring radius, the deployment points of sensors in the key protection area and the corresponding discrete coverage points are determined; including: Step S31: Select a regional point from the set of points in the key protection area, determine the distance between the regional point and each candidate point in the set of candidate sensor points, and obtain the shortest distance corresponding to the regional point in the current iteration; Step S32: If the shortest distance is less than or equal to the sensor detection radius, the candidate point corresponding to the shortest distance is used as the deployment point of the sensor in the key protection area, and the coverage discrete point corresponding to the deployment point is determined. Step S33: Delete the aforementioned regional points from the point set of the key protection area in the current iteration; update the candidate sensor point set according to the deployment points of the sensors in the key protection area, and update the total set of discrete points of the gas pipeline according to the coverage discrete points corresponding to the deployment points; Step S34: Determine whether there are still location points in the set of locations of the key protection area. If there are still location points, return to step S31 for the next iteration until there are no location points in the set of locations of the key protection area. The total set of discrete points for gas pipelines is updated based on the coverage discrete points corresponding to the sensor deployment points in key protection areas; and the set of candidate sensor points is updated based on the sensor deployment points in key protection areas. Based on an improved greedy algorithm, a point is sequentially selected from the candidate sensor location set as a deployment point for sensors in non-key protection areas, until all sensors to be deployed are completed, thus obtaining the deployment points for sensors in non-key protection areas; including: Step S41: Determine the coverage discrete point corresponding to each candidate point in the candidate sensor point set, and take the candidate point with the most corresponding coverage discrete points as a deployment point of the sensor in the non-key protection area of ​​the current iteration. Step S42: Update the candidate sensor location set according to the deployment locations of sensors in the non-key protection areas of the current iteration; update the total set of discrete points of the gas pipeline according to the coverage discrete points corresponding to the deployment locations of sensors in the non-key protection areas of the current iteration. Step S43: Determine whether the sensors to be deployed have been deployed. If not, return to step S41 for the next iteration. If the deployment is complete, end the loop.

2. The deployment method according to claim 1, characterized in that, The determination of the coverage discrete point corresponding to each candidate point in the candidate sensor point set includes: Using the location of each candidate sensor point in the candidate sensor point set as the center, and a multiple of the sensor monitoring radius as the radius, a circular coverage area for each candidate point is obtained; the range of a is [0.75-1.25]. The discrete points covered by the circular coverage area of ​​each candidate point are taken as the corresponding coverage discrete points of each candidate point.

3. The deployment method according to claim 2, characterized in that, The step of updating the candidate sensor location set based on the deployment locations of sensors in non-key protection areas in the current iteration includes: deleting the deployment locations of sensors in non-key protection areas in the current iteration from the candidate sensor location set. The step of updating the total set of discrete points for gas pipelines based on the coverage discrete points corresponding to the deployment points of sensors in non-key protection areas in the current iteration includes: deleting the coverage discrete points corresponding to the deployment points of sensors in non-key protection areas in the current iteration from the total set of discrete points for gas pipelines.

4. The deployment method according to claim 1, characterized in that, The discretization of the gas pipeline network, resulting in the total set of discrete points for the corresponding gas pipelines, includes: For each pipeline segment in the gas pipeline network, when the length of the pipeline segment is less than or equal to the preset length, the two pipe points of the pipeline segment are taken as the discrete points corresponding to the pipeline segment. When the length of the pipeline segment is greater than the preset length, starting from any one of the two pipe points of the pipeline segment, a new discrete point is obtained every preset length. All the new discrete points of the pipeline segment and the two pipe points of the pipeline segment are used as the discrete points corresponding to the pipeline segment. The discrete points corresponding to all pipeline segments in the gas pipeline network are taken as the total set of discrete points of the gas pipeline.

5. The deployment method according to claim 1, characterized in that, Determining the coverage discrete points corresponding to the deployment point includes: Using the location of the deployment point as the center and the sensor monitoring radius as the radius, a circular coverage area of ​​the deployment point is obtained. The discrete points covered by the circular coverage area of ​​the deployment point are taken as the corresponding discrete coverage points of the deployment point.

6. The deployment method according to claim 1, characterized in that, The step of updating the total set of discrete points of the gas pipeline based on the coverage discrete points corresponding to the original sensor points includes: deleting the coverage discrete points corresponding to the original sensor points in the total set of discrete points of the gas pipeline. The step of updating the candidate sensor point set based on the original sensor points includes: deleting the original sensor points from the candidate sensor point set.

7. The deployment method according to any one of claims 1-6, characterized in that, The deployment method also includes: Once all the sensors to be deployed have been deployed, the total number of discrete coverage points is determined based on the coverage discrete points corresponding to the original sensor deployment points, the coverage discrete points corresponding to the sensor deployment points in key protection areas, and the coverage discrete points corresponding to the sensor deployment points in non-key protection areas. The monitoring coverage rate at the end of the deployment is determined based on the total number of discrete points covered and the total number of discrete points in the total set of discrete points for gas pipelines.

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