A public place fire risk assessment method and system

Abstract

The application relates to the field of fire risk assessment, in particular to a public place fire risk assessment method and system, which constructs a communication channel attenuation model through high-temperature smoke interference parameters of a target place and calculates comprehensive signal attenuation coefficients of different spatial positions of the target place; carries out dynamic interference analysis on a multi-mode communication network of the target place according to the comprehensive signal attenuation coefficients to obtain a communication system stability coefficient; combines the communication system stability coefficient with historical fire data analysis to obtain a communication topology vulnerability atlas of the target place under high-temperature smoke interference, and obtains a risk assessment result of the target place according to the communication topology vulnerability atlas. The method effectively improves the fire communication system risk assessment accuracy of the public place under high-temperature smoke interference and improves the public place fire safety guarantee level.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fire risk assessment, in particular to a public place fire risk assessment method and system. BACKGROUND

[0002] In modern public places, the personnel are dense and the building structure is complex. Once a fire occurs, the high-temperature smoke will spread rapidly, causing serious interference to the fire communication system, which may lead to communication signal attenuation and interruption, and further affect the effective development of key links such as fire command and dispatch, personnel evacuation guidance, and emergency rescue, greatly increasing the risk of life and property loss caused by fire.

[0003] At present, the traditional fire risk assessment method mainly focuses on building structure, fire fighting equipment, and personnel evacuation capacity, and the influence of high-temperature smoke on the fire communication system is relatively weak. In actual fire scenes, due to the dynamic change characteristics of high-temperature smoke, the parameters such as high-temperature and smoke concentration at different spatial positions are significantly different, which will lead to complex attenuation rules of communication signals in different areas. However, the existing communication system evaluation model is often difficult to accurately depict the attenuation characteristics of the communication channel in such a complex environment, and cannot accurately reflect the actual performance of the communication system under the interference of high-temperature smoke, thereby providing accurate risk assessment results and decision-making basis for fire management personnel.

[0004] Therefore, there is an urgent need for a public place fire risk assessment method that can comprehensively consider the high-temperature smoke interference parameters and the characteristics of multi-modal communication networks, to improve the level of fire safety in public places. SUMMARY

[0005] (1) Technical problem to be solved

[0006] The purpose of the present application is to provide a public place fire risk assessment method and system, which solves the problem of inaccurate fire communication system risk assessment in public places under the interference of high-temperature smoke.

[0007] (2) Technical scheme

[0008] To achieve the above-mentioned purpose, on the one hand, the present application provides a public place fire risk assessment method, which comprises:

[0009] S1, constructing a communication channel attenuation model according to the high-temperature smoke interference parameters of the target place, and calculating the comprehensive signal attenuation coefficient of different spatial positions in the target place through the communication channel attenuation model.

[0010] S2, performing dynamic interference analysis on the multi-modal communication network of the target place according to the comprehensive signal attenuation coefficient to obtain a communication system stability coefficient.

[0011] S3, combine the communication system stability coefficient with historical fire data analysis to obtain the communication topology vulnerability graph of the target site under high temperature smoke interference, and obtain the risk assessment result of the target site according to the communication topology vulnerability graph.

[0012] Further, the method for constructing a communication channel attenuation model according to the high-temperature smoke interference parameters of the target site includes:

[0013] According to the temperature distribution data in the high-temperature smoke interference parameters and the thermal expansion coefficient of the metal parts of the communication equipment, the thermal expansion deformation of the metal structure of the communication equipment in the high-temperature environment is calculated, and the optical signal transmission loss correction function is established in combination with the temperature-dependent refractive index of the optical fiber.

[0014] According to the smoke concentration gradient data and the smoke particle size distribution data in the high-temperature smoke interference parameters, the scattering attenuation coefficient of the preset millimeter wave frequency band electromagnetic wave in the smoke environment is calculated.

[0015] The optical signal transmission loss correction function and the scattering attenuation coefficient are coupled to generate a communication channel attenuation model.

[0016] The target site is divided into spatial grid units of a preset precision, and the high-temperature smoke interference parameters of the corresponding position are loaded for each grid unit; the signal attenuation amount of the multi-band signal of each grid unit is calculated according to the communication channel attenuation model, and the signal attenuation amount of the multi-band signal in the same grid unit is weighted and fused to obtain the comprehensive signal attenuation coefficient according to the preset communication link priority weight of the target site.

[0017] Further, the method for dynamically analyzing the multi-modal communication network of the target site according to the comprehensive signal attenuation coefficient to obtain the communication system stability coefficient includes:

[0018] A dynamic interference matrix is constructed according to the comprehensive signal attenuation coefficient, the survival rate of the redundant communication links in the redundant communication links is calculated according to the dynamic interference matrix, the comprehensive signal attenuation coefficient of the key communication node is extracted, and the invulnerability score of the key communication node is calculated in combination with the preset communication node fire resistance level parameter and the heat dissipation efficiency parameter; the maximum recovery delay time is calculated according to the switching delay time and the signal recovery stable time of the backup link by simulating the failure scenario of the main communication link.

[0019] The communication system stability coefficient is calculated by normalizing the survival rate of the redundant communication links, the invulnerability score, and the maximum recovery delay time.

[0020] Further, the method for combining the communication system stability coefficient with historical fire data to analyze the communication topology vulnerability graph of the target site under high-temperature smoke interference includes:

[0021] According to the communication system stability coefficient, the risk level of the grid unit is divided; the historical cases matching the fire simulation parameters of the target site in the historical fire data are obtained, and the correlation degree weight of the current scene and the historical cases is calculated through a similarity algorithm; and the fire risk probability prediction value of the current scene is obtained by weighting and fusing the communication interruption duration, equipment damage rate and personnel evacuation delay data in the historical cases according to the correlation degree weight.

[0022] According to the risk level and the fire risk probability prediction value, a communication topology vulnerability graph is generated and transmitted to the visualization terminal of the fire management platform to obtain the risk assessment result.

[0023] Further, the method for constructing a dynamic interference matrix according to the comprehensive signal attenuation coefficient and calculating the survival rate of the redundant communication link in the redundant communication link includes:

[0024] According to the multi-modal communication network of the target site, a communication node-link topology structure is obtained, wherein the communication node corresponds to the deployment position of the communication equipment, and the link represents the communication connection between the communication nodes; the row of the dynamic interference matrix corresponds to the communication node, and the column corresponds to the preset communication frequency band; the element value of the dynamic interference matrix is calculated through the comprehensive signal attenuation coefficient of the preset communication frequency band of the communication node and the priority weight of the preset communication frequency band.

[0025] The survival state of the redundant communication link is calculated, and the survival state determination criterion is that the element values of the dynamic interference matrix of the communication nodes at both ends of the communication link are lower than a preset attenuation threshold; and the survival rate of the redundant link is calculated according to the ratio of the number of redundant links maintaining the survival state to the total number of redundant links within a preset time window.

[0026] On the other hand, based on the same inventive concept, the present application also provides a public place fire risk assessment system, which comprises: a comprehensive signal attenuation coefficient generation module, a communication system stability coefficient acquisition module and a risk assessment management module, which are sequentially and communicatively connected;

[0027] The comprehensive signal attenuation coefficient generation module is used for constructing a communication channel attenuation model according to the high-temperature smoke interference parameters of the target site, and calculating the comprehensive signal attenuation coefficient of different spatial positions of the target site through the communication channel attenuation model.

[0028] The communication system stability coefficient acquisition module is used for performing dynamic interference analysis on the multi-modal communication network of the target site according to the comprehensive signal attenuation coefficient to obtain the communication system stability coefficient.

[0029] a risk assessment management module, configured to combine the communication system stability coefficient with historical fire data to analyze a communication topology vulnerability graph of the target site under high-temperature smoke interference, and obtain a risk assessment result of the target site according to the communication topology vulnerability graph.

[0030] Further, the comprehensive signal attenuation coefficient generation module comprises the following steps:

[0031] According to the temperature distribution data in the high-temperature smoke interference parameter and the thermal expansion coefficient of the metal part of the communication equipment, the thermal expansion deformation of the metal structure of the communication equipment in the high-temperature environment is calculated, and a light signal transmission loss correction function is established in combination with the temperature dependence parameter of the refractive index of the optical fiber.

[0032] According to the smoke concentration gradient data and the smoke particle size distribution data in the high-temperature smoke interference parameter, the scattering attenuation coefficient of the preset millimeter wave frequency band electromagnetic wave in the smoke environment is calculated.

[0033] The light signal transmission loss correction function and the scattering attenuation coefficient are coupled to generate a communication channel attenuation model.

[0034] The target site is divided into spatial grid units of a preset precision, and the high-temperature smoke interference parameters of the corresponding positions are loaded for each grid unit; the signal attenuation amount of the multi-frequency band signal of each grid unit is calculated according to the communication channel attenuation model, and the signal attenuation amounts of the multi-frequency band signals in the same grid unit are weighted and fused according to the preset communication link priority weight of the target site to obtain a comprehensive signal attenuation coefficient.

[0035] Further, the communication system stability coefficient acquisition module comprises:

[0036] The data acquisition module is configured to construct a dynamic interference matrix according to the comprehensive signal attenuation coefficient, to statistically obtain a redundant link survival rate in a redundant communication link according to the dynamic interference matrix, to extract the comprehensive signal attenuation coefficient of a key communication node, to calculate an invulnerability score of the key communication node in combination with a preset communication node fire resistance level parameter and a heat dissipation efficiency parameter, and to calculate a maximum recovery delay time according to a switching delay time and a signal recovery stable time of a backup link in a simulation of a main communication link failure scenario.

[0037] The communication system stability coefficient calculation submodule is configured to calculate the communication system stability coefficient after normalization of the redundant link survival rate, the invulnerability score and the maximum recovery delay time.

[0038] Further, the risk assessment management module comprises the following steps:

[0039] According to the communication system stability coefficient, the risk level of the grid unit is divided; the historical case matching the fire simulation parameter of the target place in the historical fire data is obtained, and the correlation degree weight of the current scene and the historical case is calculated through a similarity algorithm; the communication interruption time, the equipment damage rate and the personnel evacuation delay data in the historical case are weighted and fused according to the correlation degree weight to obtain the fire risk probability prediction value of the current scene.

[0040] According to the risk level and the fire risk probability prediction value, a communication topology vulnerability map is generated and transmitted to a visualization terminal of a fire management platform to obtain a risk assessment result.

[0041] Further, the data acquisition module comprises the following steps:

[0042] According to the multi-modal communication network of the target place, a communication node-link topology structure is obtained, wherein the communication node corresponds to the deployment position of the communication equipment, and the link represents the communication connection between the communication nodes; the row of the dynamic interference matrix corresponds to the communication node, and the column corresponds to the preset communication frequency band; the dynamic interference matrix element value is calculated through the comprehensive signal attenuation coefficient of the preset communication frequency band of the communication node and the preset communication frequency band priority weight.

[0043] The survival state of the redundant communication link is counted, and the survival state determination criterion is that the dynamic interference matrix element values of the communication nodes at both ends of the communication link are lower than the preset attenuation threshold; the redundant link survival rate is calculated according to the ratio of the number of redundant links maintaining the survival state in the preset time window to the total number of redundant links.

[0044] (3) Advantageous effects

[0045] Compared with the prior art, the advantageous effects of the present application are:

[0046] 1. By constructing a communication channel attenuation model, combining high-temperature smoke interference parameters, accurately calculating the comprehensive signal attenuation coefficient of different spatial positions of the target place, and comprehensively analyzing the dynamic characteristics of the multi-modal communication network under high-temperature smoke interference, a reliable basis is provided for accurately evaluating the stability of the communication system.

[0047] 2. According to the dynamic interference matrix constructed according to the comprehensive signal attenuation coefficient, the survival rate of the redundant link, the anti-destroyability score of the key communication node and the maximum recovery delay time and other factors are comprehensively considered, the communication system stability coefficient is calculated by normalization, and the stability of the communication system is comprehensively and quantitatively evaluated.

[0048] 3. By combining the stability coefficient of the communication system with historical fire data and using a similarity algorithm to calculate the correlation weight, the historical case data is weighted and fused to generate a communication topology vulnerability map and transmit it to a visualization terminal. This provides an intuitive presentation of the fire risk assessment results of the target site, helping fire management personnel to quickly and accurately understand the site's risk status and take timely and effective measures. Attached Figure Description

[0049] Figure 1 This is a flowchart of a fire risk assessment method for public places according to Embodiment 1 of the present invention.

[0050] Figure 2 This is a schematic diagram of the module composition of a public place fire risk assessment system according to Embodiment 2 of the present invention. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] Before providing examples, it is necessary to explain the application scenarios of the present invention. The present invention is a method and system for fire risk assessment in public places, which addresses the challenge of risk assessment of fire communication systems under high temperature and smoke interference in public places, and improves the level of fire safety assurance in public places.

[0053] Example 1: As Figure 1 As shown in the figure, this embodiment provides a method for fire risk assessment in public places, the method including:

[0054] S1. A communication channel attenuation model is constructed based on the high-temperature smoke interference parameters of the target location. The comprehensive signal attenuation coefficient at different spatial locations within the target location is calculated using this model. Taking a large commercial complex as an example, the building is equipped with a multi-modal fire communication system integrating fiber optic communication networks, digital trunking communication systems, and WiFi wireless signal coverage for emergency command and dispatch, evacuation guidance, and rescue coordination during a fire. Based on parameters such as the building structure, decoration material characteristics, and ventilation system layout of the commercial complex, a high-temperature smoke interference parameter set is generated using fire simulation software. This set includes spatial temperature distribution data, smoke concentration gradient data, and smoke particle size distribution data, reflecting how high-temperature smoke diffuses and affects the physical environment of communication signals when a fire occurs at different locations within the building. The communication channel attenuation model comprehensively considers the impact mechanism of the high-temperature environment on the transmission characteristics of metal wires, optical fibers, and electromagnetic waves, and can calculate the comprehensive signal attenuation coefficient at any location within the building.

[0055] S2, performing dynamic interference analysis on the multi-modal communication network of the target site according to the comprehensive signal attenuation coefficient to obtain a communication system stability coefficient; simulating the whole process of fire spreading from the ignition point, evaluating the continuous impact of high-temperature smoke on each communication node and link, and calculating the communication system stability coefficient at different time points. For example, in the simulated scenario, 15 minutes after the fire occurs, the communication system stability coefficient decreases from the initial value of 0.95 to 0.68, indicating that the system performance has decreased significantly but still maintains basic functions.

[0056] S3, combining the communication system stability coefficient with historical fire data analysis to obtain a communication topology vulnerability map of the target site under the interference of high-temperature smoke, and obtaining the risk assessment result of the target site according to the communication topology vulnerability map. The communication topology vulnerability map is rendered based on the building information model (BIM) to generate a three-dimensional risk heat map, which visually displays the communication risk level of each area in the building in a three-dimensional visualization manner, and identifies the weak links and potential failure points of the key communication nodes. For example, the communication topology vulnerability map shows that the communication coverage of the atrium area and the emergency evacuation staircase in the shopping mall has high vulnerability, and the deployment of backup communication nodes needs to be strengthened, and a risk assessment report is generated to provide targeted optimization suggestions for fire management personnel, including adding hot backup nodes, adjusting the communication network topology structure, upgrading the heat resistance level of key position equipment, etc.

[0057] The method for constructing a communication channel attenuation model according to the high-temperature smoke interference parameters of the target site, and calculating the comprehensive signal attenuation coefficient of different spatial positions of the target site through the communication channel attenuation model comprises:

[0058] The thermal expansion deformation of the metal structure of the communication device under high-temperature environment is calculated according to the temperature distribution data in the high-temperature smoke interference parameter and the thermal expansion coefficient of the metal part of the communication device, and a light signal transmission loss correction function is established in combination with the temperature dependence parameter of the refractive index of the optical fiber; the thermal expansion deformation of the metal structure of the communication device under high-temperature environment is calculated through a thermodynamic expansion equation, the thermodynamic expansion equation is ΔL = α·L0·ΔT, where ΔL is the thermal expansion deformation, α is the thermal expansion coefficient of the metal (for example, the thermal expansion coefficient of copper is about 16.5×10^-6 / ℃, and the thermal expansion coefficient of aluminum is about 23×10^-6 / ℃), L0 is the initial length of the metal structure at normal temperature, and ΔT is the difference between the current temperature and the normal temperature; the optical fiber bending loss increment is calculated according to the thermal expansion deformation, the bending loss increment is determined through an optical fiber micro-bending loss model, and the optical fiber micro-bending loss model satisfies δL = K·(ΔL / L0)^2, where K is a preset optical fiber bending sensitivity coefficient; a temperature-refractive index change relationship n(T) = n0 + β·ΔT is established according to the temperature dependence parameter of the refractive index of the optical fiber, n0 is the refractive index at normal temperature, β is the thermo-optic coefficient of the optical fiber material, ΔT is the difference between the current temperature and the normal temperature, and the transmission loss offset caused by the refractive index fluctuation is calculated; the bending loss increment and the transmission loss offset are fused according to a linear superposition model to generate an optical signal transmission loss correction function L(T) = δL + γ·|n(T)-n0|, where γ is a refractive index loss weight factor, which is determined through an optical fiber type calibration experiment. The thermal expansion deformation of the metal structure of the communication device interface, connector and the like under different temperatures is calculated. For example, under a high-temperature environment of 800℃, the length of the copper connector will increase by about 1.3%, which will cause a slight misalignment and poor contact at the interface. At the same time, the refractive index of the optical fiber itself will also change with temperature, and the temperature dependence parameter of the quartz optical fiber is about 6×10^-6 / ℃.

[0059] The scattering attenuation coefficient of the preset millimeter wave frequency band electromagnetic wave in the smoke environment is calculated according to the smoke concentration gradient data and the smoke particle size distribution data in the high-temperature smoke interference parameter; for a radio signal, the scattering attenuation coefficient of the millimeter wave frequency band (such as the 24GHz and 28GHz frequency bands used by 5G communication) electromagnetic wave in the smoke environment is calculated based on the Mie scattering theory, using the smoke particle size distribution data (such as the smoke particle diameter in the range of 0.1-10μm generated by a typical fire) and the concentration gradient data (such as the corresponding relationship between visibility and smoke mass concentration). The scattering attenuation coefficient S(ρ,d) is a function of the smoke concentration ρ and the particle size distribution d, which is obtained by fitting the experimental data.

[0060] The optical signal transmission loss correction function and the scattering attenuation coefficient are coupled to generate a communication channel attenuation model;

[0061] The target site is divided into spatial grid units of a preset precision, and high-temperature smoke interference parameters corresponding to the positions of each grid unit are loaded; the signal attenuation amount of the multi-band signal of each grid unit is calculated according to the communication channel attenuation model, and the signal attenuation amount of the multi-band signal in the same grid unit is weighted and fused according to the preset communication link priority weight of the target site to obtain a comprehensive signal attenuation coefficient. For example, the target site is divided into spatial grid units of 1m×1m×1m, and each grid unit loads corresponding temperature values, smoke concentration values and particle distribution values from the fire simulation according to its position. Then, the signal attenuation amount of the multi-band signal (including 850nm, 1310nm and 1550nm wavelengths used by optical fibers, and 400MHz, 2.4GHz and 5GHz frequency bands used by wireless communication) of each grid unit is calculated respectively. According to the importance of each frequency band in fire-fighting communication, the weights are set, such as 0.5 for emergency command and dispatching communication, 0.3 for evacuation guiding communication, and 0.2 for monitoring data transmission. The attenuation amounts of the multi-band signals in the same grid unit are weighted and fused to obtain a comprehensive signal attenuation coefficient.

[0062] The method for dynamically analyzing the multi-modal communication network of the target site according to the comprehensive signal attenuation coefficient to obtain a communication system stability coefficient comprises:

[0063] According to the comprehensive signal attenuation coefficient, a dynamic interference matrix is constructed, and a redundant link survival rate in a redundant communication link is counted according to the dynamic interference matrix; a comprehensive signal attenuation coefficient of a key communication node is extracted, and a damage resistance score of the key communication node is calculated in combination with a preset communication node fire resistance level parameter and a heat dissipation efficiency parameter; a maximum recovery delay time is calculated according to a switching delay time and a signal recovery stable time of a backup link in a simulation of a main communication link failure scenario; the dimension of the dynamic interference matrix is m*n, wherein m represents the number of communication nodes, such as 128 communication nodes deployed in the commercial complex, and n represents the number of preset communication frequency bands, such as 6 frequency bands of optical fibers and wireless. In the commercial complex, double-redundant or triple-redundant communication links are deployed in key areas (such as evacuation channels and safety exits). Meanwhile, the comprehensive signal attenuation coefficient of 35 key communication nodes such as a central control room, a floor sub-control point and an evacuation guide system is extracted, and the damage resistance score of the key communication node is calculated in combination with the fire resistance level parameter of these devices, such as the A-level fire resistance of the central control room device, which can normally work for 30 minutes in a 200℃ environment, and the heat dissipation efficiency parameter, such as the heat dissipation efficiency of 85% of the device with forced air cooling. The score adopts a 0-100 point system, such as the score of 85 points of the core switching device of the central control room, indicating a higher anti-interference capability. The switching response capability of the backup link is evaluated by simulating the failure scenario of the main communication link. For example, when the main optical fiber link connecting the evacuation channel fails due to excessive temperature, it needs to be automatically switched to the backup wireless link. Tests show that the average delay time of such switching is 1.2 seconds, the signal recovery stable time is 3.5 seconds, and therefore the maximum recovery delay time is 4.7 seconds, which is lower than the safety standard requirement of 5 seconds.

[0064] After normalization of the redundant link survival rate, the damage resistance score and the maximum recovery delay time, a communication system stability coefficient is calculated. The redundant link survival rate (valued at 0-1), the damage resistance score (normalized to 0-1) and the maximum recovery delay time (the reciprocal of the normalized value, valued at 0-1) are weighted and averaged to obtain the communication system stability coefficient S = 0.4 x R + 0.4 x D + 0.2 x (1-T'), wherein R is the redundant link survival rate, D is the normalized damage resistance score, and T' is the normalized maximum recovery delay time.

[0065] The method for obtaining the risk assessment result of the target site according to the communication topology vulnerability map under high-temperature smoke interference of the target site according to the communication system stability coefficient combined with historical fire data comprises:

[0066] According to the communication system stability coefficient, the risk level of the grid unit is divided; the historical case matching the fire simulation parameters of the target site is obtained from the historical fire data, and the correlation degree weight of the current scene and the historical case is calculated through the similarity algorithm; the communication interruption time, equipment damage rate and personnel evacuation delay data in the historical case are weighted and fused to obtain the fire risk probability prediction value of the current scene according to the correlation degree weight. In the process of generating the communication topology vulnerability map, the risk level of each grid unit is divided according to the communication system stability coefficient. Specifically, the stability coefficient is divided into five levels: safe (0.8-1.0), low risk (0.6-0.8), medium risk (0.4-0.6), high risk (0.2-0.4) and extremely high risk (0-0.2). In this way, each space position in the building is given a risk level identification. At the same time, the fire cases similar to the target site conditions are retrieved from the fire historical database. The database contains detailed records of more than 2000 public place fires in the country in the past five years, including building type, scale, fire location, fire spread speed, communication system damage, etc. Through the multidimensional similarity algorithm, the correlation degree weight of the current scene and the historical case is calculated. For example, for this commercial complex, 15 high similarity cases are matched, of which the similarity with a shopping center fire case is the highest, and the correlation degree weight is 0.25. According to these correlation degree weights, the communication interruption time (such as an average of 42 minutes), equipment damage rate (such as an average of 31%) and personnel evacuation delay data (such as an average of 4.5 minutes of increased evacuation time) recorded in the historical cases are weighted and fused to obtain the fire risk probability prediction value of the current scene. These prediction values show that in the simulated fire scenario, the probability of complete communication system interruption of the commercial complex is 15%, the probability of key equipment damage is 22%, and the personnel evacuation time may be extended by 3.2 minutes.

[0067] According to the risk level and the fire risk probability prediction value, a communication topology vulnerability map is generated and transmitted to the visualization terminal of the fire management platform to obtain the risk assessment result. The communication topology vulnerability map uses color coding (green to red representing low to high risk) to intuitively show the communication risk status of each area in the building, and uses special icons to mark the key communication nodes and potential failure points. The communication topology vulnerability map is displayed to the management personnel through the visualization terminal of the fire management platform, supporting interactive query and risk analysis. For example, the management personnel can click on a specific area to view the risk assessment details of the area, including the expected communication interruption time, the number of affected personnel, etc. According to the risk assessment result, a targeted optimization suggestion report is generated, such as adding two redundant communication nodes in the fourth floor cinema area, upgrading the heat resistance level of the wireless base station in the atrium area, adjusting the topology structure of part of the communication link to improve the network resilience, etc. These suggestions are sorted and marked with implementation priority and expected risk reduction effect, providing a scientific basis for fire management decision-making.

[0068] The method for constructing a dynamic interference matrix according to the comprehensive signal attenuation coefficient, and calculating the redundancy link survival rate in the redundant communication link according to the dynamic interference matrix comprises:

[0069] The communication node-link topology structure is obtained according to the multi-modal communication network of the target site, wherein the communication node corresponds to the deployment position of the communication equipment, and the link represents the communication connection between the communication nodes; the row of the dynamic interference matrix corresponds to the communication node, and the column corresponds to the preset communication frequency band; the element value of the dynamic interference matrix is calculated through the comprehensive signal attenuation coefficient of the preset communication frequency band of the communication node and the priority weight of the preset communication frequency band; and the complete communication node-link topology structure is obtained by scanning the communication equipment deployment graph and the network topology graph of the commercial complex. The communication node-link topology structure is represented as a graph G(V, E) in graph theory, wherein the vertex set V represents 128 communication nodes (such as control room equipment, floor sub-control points, wireless access points, etc.), and the edge set E represents 256 communication links (such as optical fiber trunks, backup network connections, etc.) between the nodes. The dynamic interference matrix D is constructed by using a location-based mapping method, the row of the dynamic interference matrix corresponds to 128 communication nodes, and the column corresponds to 6 preset communication frequency bands, for example, including 3 optical fiber wavelengths and 3 wireless frequency bands. Each element D(i, j) in the dynamic interference matrix represents the interference degree of the communication node i on the frequency band j, and the calculation formula is D(i, j) = A(i) x W(j), wherein A(i) is the comprehensive signal attenuation coefficient of the position of the communication node i, and W(j) is the priority weight of the frequency band j.

[0070] The survival state of the statistical redundant communication link is determined according to the dynamic interference matrix element values of the communication nodes at both ends of the communication link being lower than a preset attenuation threshold value; and the survival rate of the redundant link is calculated according to the ratio of the number of redundant links maintaining the survival state in a preset time window to the total number of redundant links. A threshold determination method is used to evaluate the survival state of the redundant communication link. For each redundant link l(i,j) (connecting communication node i and communication node j), if the dynamic interference matrix element values D(i,k) and D(j,k) of the communication nodes at both ends of the link on the working frequency band k are both lower than the preset attenuation threshold value θ(k) (for example, the threshold value of the optical fiber link is 0.7, and the threshold value of the wireless link is 0.6), it is considered that the link is in the survival state. In order to reflect the dynamic changes of the communication network state in the fire development process, a 10-minute evaluation time window is set, and the survival state is evaluated every 30 seconds, generating 20 network state snapshots at time points. At each time point t, the survival rate R(t) of the redundant link is calculated, where N(t) is the number of redundant links surviving at time t, and M is the total number of redundant links (the commercial complex has a total of 78 redundant links). For example, in the simulated scenario, after 3 minutes of fire, the survival rate of the redundant link is 0.92; after 6 minutes, due to the spread of high-temperature smoke to more areas, the survival rate decreases to 0.78; and after 10 minutes, the temperature in some areas exceeds the heat resistance upper limit of the equipment, and the survival rate further decreases to 0.65. These data provide an important basis for subsequent communication system stability coefficient calculation and risk assessment.

[0071] Embodiment 2: based on the same inventive concept, as shown in Figure 2 The embodiment also provides a public place fire risk assessment system, which comprises: a comprehensive signal attenuation coefficient generation module, a communication system stability coefficient acquisition module, and a risk assessment management module, which are sequentially and communicatively connected;

[0072] The comprehensive signal attenuation coefficient generation module is configured to construct a communication channel attenuation model according to high-temperature smoke interference parameters of a target place, and calculate comprehensive signal attenuation coefficients of different spatial positions of the target place through the communication channel attenuation model.

[0073] The communication system stability coefficient acquisition module is configured to perform dynamic interference analysis on a multi-modal communication network of the target place according to the comprehensive signal attenuation coefficients to obtain a communication system stability coefficient.

[0074] The risk assessment management module is configured to combine the communication system stability coefficient with historical fire data analysis to obtain a communication topology vulnerability map of the target place under high-temperature smoke interference, and obtain a risk assessment result of the target place according to the communication topology vulnerability map.

[0075] The comprehensive signal attenuation coefficient generation module comprises the following steps:

[0076] The thermal expansion deformation variable of the metal structure of the communication equipment under the high-temperature environment is calculated according to the temperature distribution data in the high-temperature smoke interference parameter and the thermal expansion coefficient of the metal part of the communication equipment, and a light signal transmission loss correction function is established in combination with the temperature dependence parameter of the refractive index of the optical fiber.

[0077] The scattering attenuation coefficient of the preset millimeter wave frequency band electromagnetic wave in the smoke environment is calculated according to the smoke concentration gradient data and the smoke particle size distribution data in the high-temperature smoke interference parameter.

[0078] The light signal transmission loss correction function is coupled with the scattering attenuation coefficient to generate a communication channel attenuation model.

[0079] The target site is divided into spatial grid units of a preset precision, and the high-temperature smoke interference parameters of the corresponding positions are loaded for each grid unit; the signal attenuation amount of the multi-band signal of each grid unit is calculated according to the communication channel attenuation model, and the signal attenuation amount of the multi-band signal in the same grid unit is weighted and fused to obtain a comprehensive signal attenuation coefficient according to the preset communication link priority weight of the target site.

[0080] The communication system stability coefficient acquisition module comprises:

[0081] The data acquisition module is configured to construct a dynamic interference matrix according to the comprehensive signal attenuation coefficient, to count the redundancy link survival rate in the redundant communication link according to the dynamic interference matrix, to extract the comprehensive signal attenuation coefficient of the key communication node, to calculate the invulnerability score of the key communication node in combination with the preset communication node fire resistance level parameter and the heat dissipation efficiency parameter, and to calculate the maximum recovery delay time according to the switching delay time and the signal recovery stable time of the backup link in a simulated main communication link failure scenario.

[0082] The communication system stability coefficient calculation submodule is configured to calculate the communication system stability coefficient by normalizing the redundancy link survival rate, the invulnerability score and the maximum recovery delay time.

[0083] The risk assessment management module comprises the following steps:

[0084] The grid unit is divided into a risk level according to the communication system stability coefficient; the historical cases matching the fire simulation parameters of the target site in the historical fire data are obtained, the correlation degree weight of the current scene and the historical cases is calculated through a similarity algorithm, and the fire risk probability prediction value of the current scene is obtained by weighted fusion of the communication interruption duration, the equipment damage rate and the personnel evacuation delay data in the historical cases according to the correlation degree weight.

[0085] According to the risk level and the fire risk probability prediction value, a communication topology vulnerability map is generated and transmitted to a visualization terminal of a fire management platform to obtain a risk assessment result.

[0086] The data acquisition module comprises the following steps:

[0087] According to the multi-modal communication network of the target site, a communication node-link topology structure is obtained, wherein the communication nodes correspond to the deployment positions of the communication devices, and the links represent the communication connections between the communication nodes; the rows of the dynamic interference matrix correspond to the communication nodes, and the columns correspond to the preset communication frequency bands; the element values of the dynamic interference matrix are calculated by the comprehensive signal attenuation coefficients of the preset communication frequency bands of the communication nodes and the preset communication frequency band priority weights.

[0088] The survival state of the redundant communication links is counted, and the survival state determination criterion is that the element values of the dynamic interference matrix of the communication nodes at both ends of the communication link are lower than a preset attenuation threshold; the survival rate of the redundant links is calculated according to the ratio of the number of redundant links maintaining the survival state to the total number of redundant links within a preset time window.

[0089] It should be noted that, as for the system in the above-mentioned embodiments, the specific manner in which each module performs operations has been described in detail in the embodiments related to the method, and will not be described in detail here.

[0090] Finally, it should be noted that: although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part of the technical features, any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for fire risk assessment in public places, characterized in that, The method includes: A communication channel attenuation model is constructed based on the high temperature smoke interference parameters of the target location, and the comprehensive signal attenuation coefficient at different spatial locations of the target location is calculated using the communication channel attenuation model. The stability coefficient of the communication system is obtained by performing dynamic interference analysis on the multimodal communication network at the target location based on the comprehensive signal attenuation coefficient. By combining the stability coefficient of the communication system with historical fire data analysis, a communication topology vulnerability map of the target site under high temperature smoke interference is obtained, and the risk assessment result of the target site is obtained based on the communication topology vulnerability map; The method for constructing a communication channel attenuation model based on the high-temperature smoke interference parameters of the target location, and calculating the comprehensive signal attenuation coefficient at different spatial locations of the target location using the communication channel attenuation model, includes: Based on the temperature distribution data in the high-temperature smoke interference parameters and the thermal expansion coefficient of the metal components of the communication equipment, the thermal expansion deformation of the metal structure of the communication equipment under high temperature environment is calculated, and the optical signal transmission loss correction function is established in combination with the optical fiber refractive index temperature dependence parameter. The scattering attenuation coefficient of electromagnetic waves in the preset millimeter-wave frequency band in the smoke environment is calculated based on the smoke concentration gradient data and smoke particle size distribution data in the high-temperature smoke interference parameters. The optical signal transmission loss correction function is coupled with the scattering attenuation coefficient to generate a communication channel attenuation model; The target location is divided into spatial grid cells with a preset precision. High-temperature smoke interference parameters corresponding to the location are loaded into each grid cell. The signal attenuation of the multi-band signals in each grid cell is calculated according to the communication channel attenuation model. The signal attenuation of the multi-band signals in the same grid cell is weighted and fused according to the preset communication link priority weight of the target location to obtain a comprehensive signal attenuation coefficient.

2. The method for fire risk assessment in public places according to claim 1, characterized in that, The method for obtaining the stability coefficient of a communication system by performing dynamic interference analysis on a multimodal communication network at a target location based on the comprehensive signal attenuation coefficient includes: A dynamic interference matrix is ​​constructed based on the comprehensive signal attenuation coefficient. The survival rate of redundant links in redundant communication links is statistically calculated based on the dynamic interference matrix. The comprehensive signal attenuation coefficient of key communication nodes is extracted, and the survivability score of key communication nodes is calculated by combining the preset fire resistance rating parameters and heat dissipation efficiency parameters of communication nodes. The failure scenario of the main communication link is simulated, and the maximum recovery delay time is calculated based on the switching delay time of the backup link and the signal recovery stabilization time. The stability coefficient of the communication system is calculated by normalizing the redundant link survival rate, resilience score, and maximum recovery delay time.

3. The method for fire risk assessment in public places according to claim 1, characterized in that, The method for obtaining a communication topology vulnerability map of the target location under high-temperature smoke interference by combining the stability coefficient of the communication system with historical fire data analysis, and obtaining the risk assessment result of the target location based on the communication topology vulnerability map, includes: The risk level of the grid cells is divided according to the stability coefficient of the communication system; historical cases that match the fire simulation parameters of the target site are obtained from historical fire data, and the correlation weight between the current scene and the historical cases is calculated by similarity algorithm; the communication interruption duration, equipment damage rate and personnel evacuation delay data in the historical cases are weighted and fused according to the correlation weight to obtain the fire risk probability prediction value of the current scene. Based on the risk level and the predicted fire risk probability value, a communication topology vulnerability map is generated and transmitted to the visualization terminal of the fire management platform to obtain the risk assessment results.

4. The method for fire risk assessment in public places according to claim 2, characterized in that, The method for constructing a dynamic interference matrix based on a comprehensive signal attenuation coefficient, and for calculating the survival rate of redundant links in redundant communication links based on the dynamic interference matrix, includes: The communication node-link topology is obtained based on the multimodal communication network of the target site, where communication nodes correspond to the deployment location of communication equipment and links represent the communication connections between communication nodes; the rows of the dynamic interference matrix correspond to communication nodes and the columns correspond to preset communication frequency bands. The element values ​​of the dynamic interference matrix are calculated by the comprehensive signal attenuation coefficient of the preset communication frequency band of the communication node and the priority weight of the preset communication frequency band. The survival status of redundant communication links is statistically analyzed. The survival status is determined by the fact that the dynamic interference matrix element values ​​of the communication nodes at both ends of the communication link are all lower than a preset attenuation threshold. The survival rate of redundant links is calculated based on the ratio of the number of redundant links that maintain survival status within a preset time window to the total number of redundant links.

5. A fire risk assessment system for public places, characterized in that, The system includes: a comprehensive signal attenuation coefficient generation module, a communication system stability coefficient acquisition module, and a risk assessment and management module, with each module connected to the other in sequence. The integrated signal attenuation coefficient generation module is used to construct a communication channel attenuation model based on the high temperature smoke interference parameters of the target location, and to calculate the integrated signal attenuation coefficient at different spatial locations of the target location through the communication channel attenuation model. The communication system stability coefficient acquisition module is used to perform dynamic interference analysis on the multimodal communication network at the target location based on the comprehensive signal attenuation coefficient to obtain the communication system stability coefficient. The risk assessment and management module is used to analyze the communication system stability coefficient in conjunction with historical fire data to obtain a communication topology vulnerability map of the target location under high temperature smoke interference, and to obtain the risk assessment result of the target location based on the communication topology vulnerability map; The integrated signal attenuation coefficient generation module includes the following steps: Based on the temperature distribution data in the high-temperature smoke interference parameters and the thermal expansion coefficient of the metal components of the communication equipment, the thermal expansion deformation of the metal structure of the communication equipment under high temperature environment is calculated, and the optical signal transmission loss correction function is established in combination with the optical fiber refractive index temperature dependence parameter. The scattering attenuation coefficient of electromagnetic waves in the preset millimeter-wave frequency band in the smoke environment is calculated based on the smoke concentration gradient data and smoke particle size distribution data in the high-temperature smoke interference parameters. The optical signal transmission loss correction function is coupled with the scattering attenuation coefficient to generate a communication channel attenuation model; The target location is divided into spatial grid cells with a preset precision. High-temperature smoke interference parameters corresponding to the location are loaded into each grid cell. The signal attenuation of the multi-band signals in each grid cell is calculated according to the communication channel attenuation model. The signal attenuation of the multi-band signals in the same grid cell is weighted and fused according to the preset communication link priority weight of the target location to obtain a comprehensive signal attenuation coefficient.

6. A public place fire risk assessment system according to claim 5, characterized in that, The communication system stability coefficient acquisition module includes: The data acquisition module is used to construct a dynamic interference matrix based on the comprehensive signal attenuation coefficient, and to calculate the survival rate of redundant links in the redundant communication links based on the dynamic interference matrix; to extract the comprehensive signal attenuation coefficient of key communication nodes, and to calculate the survivability score of key communication nodes by combining the preset fire resistance rating parameters and heat dissipation efficiency parameters of communication nodes; to simulate the failure scenario of the main communication link, and to calculate the maximum recovery delay time based on the switching delay time of the backup link and the signal recovery stabilization time. The communication system stability coefficient calculation submodule is used to calculate the communication system stability coefficient after normalization based on the redundant link survival rate, resilience score, and maximum recovery delay time.

7. A public place fire risk assessment system according to claim 5, characterized in that, The risk assessment and management module includes the following steps: The risk level of the grid cells is divided according to the stability coefficient of the communication system; historical cases that match the fire simulation parameters of the target site are obtained from historical fire data, and the correlation weight between the current scene and the historical cases is calculated by similarity algorithm; the communication interruption duration, equipment damage rate and personnel evacuation delay data in the historical cases are weighted and fused according to the correlation weight to obtain the fire risk probability prediction value of the current scene. Based on the risk level and the predicted fire risk probability value, a communication topology vulnerability map is generated and transmitted to the visualization terminal of the fire management platform to obtain the risk assessment results.

8. A public place fire risk assessment system according to claim 6, characterized in that, The data acquisition module includes the following steps: The communication node-link topology is obtained based on the multimodal communication network of the target site, where communication nodes correspond to the deployment location of communication equipment and links represent the communication connections between communication nodes; the rows of the dynamic interference matrix correspond to communication nodes and the columns correspond to preset communication frequency bands. The element values ​​of the dynamic interference matrix are calculated by the comprehensive signal attenuation coefficient of the preset communication frequency band of the communication node and the priority weight of the preset communication frequency band. The survival status of redundant communication links is statistically analyzed. The survival status is determined by the fact that the dynamic interference matrix element values ​​of the communication nodes at both ends of the communication link are all lower than a preset attenuation threshold. The survival rate of redundant links is calculated based on the ratio of the number of redundant links that maintain survival status within a preset time window to the total number of redundant links.

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