A method and system for scoring the safety quality of drinking water

Abstract

The application discloses a kind of drinking water safety quality scoring methods, comprising: constructing multilevel evaluation index system, and collecting the monitoring data of each water quality index;According to the monitoring data, the compliance of each water quality index is determined, and the basic score of each water quality index in the health level and the sensory level is calculated using a nonlinear formula;The improved AHP analytic hierarchy process is used to determine the health comprehensive weight and the sensory comprehensive weight of each water quality index;According to the basic score of each water quality index in the health level and the sensory level and the corresponding comprehensive weight, the health level score and the sensory level score are obtained by weighted summation, and the final comprehensive water quality safety score is calculated by introducing a penalty mechanism.The application solves the shortcomings of traditional water quality evaluation methods systematically through multidimensional index design, objective weight calculation, fine scoring mechanism, standard coordination and visual result output, and provides a scientific and efficient quantitative tool for drinking water safety management.

Description

Technical Field

[0001] This invention relates to the field of scoring methods, specifically to a method and system for scoring the safety and quality of drinking water. Background Technology

[0002] Drinking water safety is a core area of ​​public health and people's livelihood, directly related to residents' health and social stability. With the advancement of water quality monitoring technology, water plants can obtain multi-level water quality indicator data (such as Escherichia coli, free chlorine, turbidity, etc.) in real time, including microbiological, physicochemical, and sensory data. However, how to conduct a scientific and unified quantitative assessment of drinking water safety and quality based on this data remains a technical challenge for the industry.

[0003] Currently, the evaluation of treated water quality faces the following main problems: First, there is a lack of a unified quantitative assessment mechanism for multi-indicator management. Traditional evaluation methods often rely on whether a single indicator meets the standard (e.g., "meeting the national standard is considered qualified"), but fail to consider the differences in health risks and sensory impacts of different indicators (for example, the pathogenicity of Escherichia coli is much higher than that of color exceeding the standard), resulting in evaluation results that cannot accurately reflect the overall water quality risk. Second, there is insufficient alignment between national standards and enterprise internal control standards. The "GB5749-2022 Standard for Drinking Water Quality" only stipulates the minimum guarantee requirements for water quality, but enterprises may set stricter internal control standards to improve water quality (e.g., the internal control standard for turbidity is 0.3 NTU, while the national standard is 1 NTU). Existing methods have not established a collaborative evaluation system between national standards and internal control standards, leading to a disconnect between enterprise management needs and standard specifications. Third, the public's demand for water quality transparency is difficult to meet. As residents become more health-conscious, they are not only concerned with whether water quality meets standards, but also require visual and communicable scoring results on how good the water quality is. However, existing evaluation methods often present a binary conclusion of "qualified / unqualified," lacking a quantitative scoring system and dynamic early warning mechanism. To address these issues, traditional technologies have attempted improvements through simple weighted summation or expert-based scoring, but these suffer from drawbacks such as subjective weight allocation, insensitivity to exceeding standards (e.g., small difference in scores between slight and severe exceedances), and a lack of dynamic adjustment mechanisms. These shortcomings fail to meet the needs of intelligent water plant management and transparent public access to information.

[0004] This invention aims to provide a method and system for scoring drinking water safety quality. By constructing a hierarchical index system, a dynamic weight calculation model, a nonlinear scoring algorithm, and a multi-level penalty mechanism, it achieves quantitative assessment and risk warning of water quality, fills the gap between engineering practice and standards and specifications, and provides a scientific and visual tool for water plant management and public communication. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for scoring the safety and quality of drinking water, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for scoring the safety quality of drinking water, characterized by comprising the following steps: Step S1: Construct a multi-level evaluation index system, which includes microbial safety indicators, physicochemical safety indicators and sensory characteristics indicators, and collect monitoring data of various water quality indicators; Step S2: Based on the monitoring data, determine whether each water quality indicator meets the standards, and use a nonlinear formula to calculate the basic scores of each water quality indicator at the health level and sensory level; Step S3: Use the improved AHP (Analytical Hierarchical Analysis) method to determine the overall health weight and overall sensory weight of each water quality indicator; Step S4: Based on the basic scores and corresponding comprehensive weights of each water quality indicator at the health level and sensory level, the health level score and sensory level score are obtained by weighted summation, and a penalty mechanism is introduced to calculate the final comprehensive water quality safety score.

[0007] Preferably, the microbiological safety indicators include Escherichia coli, total coliforms, thermotolerant coliforms, and total bacterial count; the physicochemical safety indicators include free chlorine, total chlorine, nitrite nitrogen, aluminum, manganese, iron, permanganate index, and ammonia nitrogen; and the sensory indicators include turbidity, color, odor and taste, visible matter, and pH value.

[0008] Preferably, the baseline scores of each water quality indicator under the health level / sensory level. Determined by the following nonlinear formula: in, This is the basic score of the i-th water quality indicator at the corresponding level. , where i is the water quality index number. At that time, it was at the health level. At the sensory level, and , , All values ​​are for the corresponding water quality indicators and at the corresponding levels. This is an indicator function that takes the value 1 if the condition is true, and 0 otherwise. These are the measured values ​​of the current water quality indicators. The limit ranges for this water quality indicator are defined in accordance with the "Standards for Drinking Water Quality" (GB 5749-2022) for the health level and in accordance with the internal control standards for water quality at the effluent level for the sensory level. The standard deviation is, and In the formula * Used to prevent calculation errors where the denominator is zero; This indicates the standard limit value corresponding to the water quality indicator, based on the measured value. and the limit range The relative position is selected based on the closest limit value.

[0009] Preferably, the improved AHP (Analytic Hierarchy Process) includes the following steps: Step S31: Construct a three-level structure model that includes a target layer, a criterion layer, and a scheme layer. The target layer is the comprehensive score of drinking water safety and quality, the criterion layer includes health risk criteria and sensory impact criteria, and the scheme layer consists of various specific water quality indicators. Step S32: Determine the importance scores of each water quality indicator under the two criteria of health risk and sensory impact based on expert scores, and construct a pairwise comparison judgment matrix using the 1-9 scale method; Step S33: Perform column normalization and row average calculation on the judgment matrix under the two criteria to obtain the basic weights of each water quality indicator in the health level and sensory level; Step S34: Calculate the maximum eigenvalue of each judgment matrix, and calculate the corresponding eigenvalue based on the maximum eigenvalue. , And complete the consistency check ( ), ensuring that the basic weights are reasonable and effective; Step S35: Multiply the preset weights of the two criteria with the basic weights of each water quality indicator to obtain the comprehensive health weight and comprehensive sensory weight of each water quality indicator.

[0010] Preferably, in step S32, determining the importance score of each water quality indicator includes: Based on the "Standards for Drinking Water Quality" (GB 5749-2022) and the drinking water safety assessment specifications, each water quality indicator was classified and its importance was determined at two levels: health risk and sensory impact. Based on the importance of each level, a 1-9 scale was used to assign importance scores to the health level and sensory level, respectively, which served as the basis for the weight calculation of the analytic hierarchy process.

[0011] Preferably, the judgment matrix under the health risk criterion / sensory impact criterion in step S32 Defined by the following expression: in, For the quantity of water quality indicators, This represents the importance ratio of the i-th water quality indicator to the j-th water quality indicator under the corresponding criteria, and the matrix... The elements in satisfy: , ,and ; Step S33 specifically includes: For the judgment matrix Sum the elements of each column and then... Each element in Divide by the sum of the elements in its column to obtain the column normalized matrix. ,and ; Calculate the column normalization matrix The arithmetic mean of each row of elements And obtain the weight matrix. The This represents the basic weight of the i-th water quality indicator under the corresponding criterion, and the basic weight under the health risk criterion is expressed as... The basic weights under the sensory risk criterion are expressed as follows: ; In step S35, the specific calculation formulas for the comprehensive health weight and comprehensive sensory weight of each water quality indicator are as follows: in, This represents the overall health weight of the i-th water quality indicator. This represents the overall sensory weight of the i-th water quality indicator; The weighting coefficient for the health level. is the weighting coefficient for the sensory level, and .

[0012] Preferably, the penalty mechanism sets differentiated penalty coefficients for different risk levels of each water quality indicator, and the final comprehensive water quality safety score formula is: in, Rate the health level. For the sensory level ratings, both are calculated in the same way and determined using the following formulas: In the formula, At that time, it was at the health level. At the sensory level; The basic score of the i-th water quality indicator at the corresponding level is obtained from step S2; The comprehensive weight of the i-th water quality indicator at the corresponding level is obtained from step S3; The penalty coefficient for the health level. The penalty coefficient for the sensory level is calculated in the same way and determined by the following formulas: In the formula, The penalty level is determined based on the importance of each water quality indicator; the smaller the number, the more important it is. The value is the penalty level corresponding to the water quality indicator with the highest importance among the exceeding indicators; The penalty is triggered by a value of 1 (any single water quality indicator exceeds the standard) or 0 (all water quality indicators meet the standard).

[0013] Preferably, in the penalty mechanism, when the penalty coefficient... Penalty coefficient when triggered .

[0014] This invention also applies for protection of a drinking water safety quality scoring system, comprising: The data acquisition module is used to collect monitoring data for various water quality indicators; The indicator judgment module is used to determine the compliance of various water quality indicators based on the monitoring data, and to calculate the basic scores of each water quality indicator at the health level and sensory level using a nonlinear formula. The weight calculation module uses an improved AHP (Analytical Hierarchical Method) to determine the overall health weight and overall sensory weight of each water quality indicator. The scoring calculation module is used to calculate the health level score and sensory level score by weighted summation based on the basic scores and corresponding comprehensive weights of various water quality indicators at the health level and sensory level, and introduces a penalty mechanism to calculate the final comprehensive water quality safety score. The results output module outputs the scoring results as numerical values, grades, and visual graphs.

[0015] Compared with the prior art, the beneficial effects of this invention are as follows: 1. This invention divides water quality indicators into three categories: microbiological, physicochemical, and sensory. It also incorporates the "GB5749-2022 Standard for Drinking Water Hygiene" (health standard) and enterprise internal control standards (sensory standard). It not only focuses on health risks (such as the pathogenicity of Escherichia coli) but also takes into account sensory experience (such as user perception of turbidity and color). Compared with the traditional evaluation model of "meeting a single indicator is qualified", it more comprehensively reflects the comprehensive risks of water quality.

[0016] 2. This invention adopts an improved AHP (Analytical Hierarchy Process) method, constructs a judgment matrix using the 1-9 scale method, and determines the weight of indicators by combining expert scoring and consistency testing, thus avoiding the subjective arbitrariness of weight allocation in traditional methods.

[0017] 3. This invention breaks down the comprehensive score into two independent levels: health risk and sensory impact, and calculates the scores separately to avoid interference from high sensory indicators (such as color intensity) on the health score.

[0018] 4. This invention is compatible with both national standards (basic health standards) and enterprise internal control standards (sensory optimization). For example, the health standard for free chlorine is 0.3-2.0 mg / L (national standard), while the internal control standard is 0.4-1.0 mg / L (determined by the enterprise). During evaluation, health indicators are based solely on national standards (ensuring a safety baseline), while sensory indicators are based on internal controls (enhancing user experience). This solves the problem of "disconnect between national standards and internal control standards" in traditional methods, providing enterprises with flexible optimization space for water quality management.

[0019] 5. This invention uses the basic rule of "full marks for meeting the standard and zero marks for exceeding the standard" to differentiate the indicators of different risk levels (such as Escherichia coli penalty level 1 and color penalty level 5), ensuring that the scores for slight exceedances (such as free chlorine not reaching the internal control) and serious exceedances (such as detection of total coliforms) are significantly different, and the results are more in line with the actual risk.

[0020] 6. The system output of this invention includes numerical scores, grade classifications, and visualization results such as trend charts and bar charts. It provides dynamic risk warnings for water plant managers and meets residents' needs for querying water quality transparency through a public platform. This realizes the transformation from "technical evaluation" to "communicable results" and significantly improves the practicality and social value of the method. Attached Figure Description

[0021] Figure 1 This is a flowchart illustrating the overall process of a drinking water safety quality scoring method according to the present invention. Detailed Implementation

[0022] This invention discloses a method for scoring the safety quality of drinking water. Based on actual monitoring data from a water plant in a certain city in May 2024, the specific steps are explained in detail to ensure the operability and verifiability of the technical solution.

[0023] Step S1: Construct a multi-level evaluation index system, which includes microbiological safety indicators, physicochemical safety indicators, and sensory characteristic indicators, and collect monitoring data for each water quality indicator. Specifically: The microbiological safety indicators include Escherichia coli, total coliforms, thermotolerant coliforms, and total colony count. The physicochemical safety indicators include free chlorine, total chlorine, nitrite nitrogen, aluminum, manganese, iron, permanganate index, and ammonia nitrogen. The sensory indicators include turbidity, color, odor and taste, visible matter, and pH value.

[0024] The water plant's SCADA system (data acquisition and monitoring system), online monitoring equipment (such as turbidity meters and residual chlorine meters), and manual sampling in the laboratory are used to collect data on the above 17 water quality indicators of the treated water at regular intervals (e.g., 2:00 AM) every day, and the following monitoring data are obtained: Escherichia coli: Not detected; Free chlorine: 0.31 mg / L; Chromaticity: 12 degrees; Other water quality indicators: Meet internal control standards.

[0025] Note: Internal control standards are explained in detail in step S2.

[0026] Step S2: Based on the monitoring data, determine whether each water quality indicator meets the standards, and use a nonlinear formula to calculate the basic scores of each water quality indicator at the health level and sensory level. Specifically: The national standard "Standards for Drinking Water Quality" (GB 5749-2022) is used as the basis for judging the health level, while the company's own internal control standards are used as the basis for judging the sensory level. The internal control standards are higher than the national standard. That is, if a water quality indicator meets the internal control standard, then it must meet the national standard.

[0027] The national standard range for the 17 water quality indicators and the internal control standard range for the effluent treatment plant in this embodiment are shown in Table 1 below (unit: mg / L, except for special indicators): Table 1 Reference Standards for Judging Water Quality Indicators According to the standards in Table 1, the three categories of indicators are judged to meet the standards and corresponding scores are assigned (the maximum score is 100 points). Since the internal control standards are higher than the national standards, based on the compliance judgment of each water quality indicator, there are three scoring situations: ① The measured values ​​are considered compliant if they are within the range of internal control standards and national standards, and both the health level and sensory level are given full marks; ② The measured value only exceeds the internal control standard range but is still within the national standard range. The health level is still given full marks, but the sensory level is given 0 marks. ③ If the measured value exceeds the national standard range, both the health level and sensory level will be assigned 0 points.

[0028] Therefore, the baseline scores for each water quality indicator under the health level / sensory level are as follows. It can be determined by the following nonlinear formula: in, This is the basic score of the i-th water quality indicator at the corresponding level. , where i is the water quality index number. At that time, it was at the health level. At the sensory level, and , , All values ​​are for the corresponding water quality indicators and at the corresponding levels. This is an indicator function that takes the value 1 if the condition is true, and 0 otherwise. These are the measured values ​​of the current water quality indicators. The limit ranges for this water quality indicator are defined in accordance with the "Standards for Drinking Water Quality" (GB 5749-2022) for the health level and in accordance with the internal control standards for water quality at the effluent level for the sensory level. The standard deviation is, and In the formula * Used to prevent calculation errors where the denominator is zero; This indicates the standard limit value corresponding to the water quality indicator, based on the measured value. and the limit range The relative position is selected based on the closest limit value.

[0029] Based on the actual monitoring data from the water treatment plant, scores were assigned to the health and sensory levels of various water quality indicators. The results are as follows: Escherichia coli: Not detected, meeting the standard, both the health level and sensory level are assigned 100 points; the standard deviation is calculated as follows: That is, the basic score for both levels of Escherichia coli is 100 points; Free chlorine: 0.31 mg / L, which meets the national standard (0.3-2.0 mg / L) but is lower than the internal control standard (0.4-1.0 mg / L). The health level is assigned 100 points, and the sensory level is assigned 0 points. The calculated standard deviation of its health level is as follows: That is, the basic score for the free chlorine health level is 96.43 points, and the basic score for the sensory level is 0 points; Color intensity: 12 degrees, conforming to national standards (≤15 degrees) but exceeding internal control standards (≤10 degrees), assigned 100 points to the health level and 0 points to the sensory level; the calculated standard deviation of its health level is as follows: That is, the basic score for the color health level is 100 points, and the basic score for the sensory level is 0 points.

[0030] Other water quality indicators for which specific monitoring data were not provided (such as Escherichia coli and nitrite nitrogen) all meet the requirements of internal control standards and national standards. The measured values ​​of total coliforms, thermotolerant coliforms, and nitrite nitrogen were all 0, and the standard deviations of these water quality indicators can be calculated using the standard deviation calculation formula. ; The measured values ​​of other indicators are far below the corresponding standard limits. The standard deviation of these indicators is calculated using the standard deviation calculation formula. ; Therefore, other water quality indicators for which specific monitoring data were not provided all received a base score of 100 in both the health and sensory levels.

[0031] Step S3: Determine the overall health weight and overall sensory weight of each water quality indicator using the improved AHP (Analytic Hierarchy Process) method. Specifically, this includes the following steps: Step S31: Construct a three-tiered structure model comprising an objective layer, a criterion layer, and a solution layer, wherein: Target layer: Comprehensive score of drinking water safety and quality; Criteria Level: Health Risk Criteria (80% weighting) and Sensory Impact Criteria (20% weighting). Scheme layer: The specific water quality indicators in the indicator system, including but not limited to the 17 water quality indicators mentioned above in this embodiment.

[0032] Step S32: Based on expert scores, determine the importance scores of each water quality indicator under the two criteria of health risk and sensory impact. Construct a pairwise comparison judgment matrix using the 1-9 scale method. Specifically: The meaning and standards of the 1-9 scale are shown in Table 2 below: Table 2 Importance Criteria for AHP (Analog-Philosophy of Hierarchy Process) For example, among the aforementioned water quality indicators, if the importance of Escherichia coli is much higher than that of color, and if the importance of color is 1, then Escherichia coli can be assigned a value of "7" or "9".

[0033] Based on the "Standards for Drinking Water Quality" (GB 5749-2022) and the drinking water safety assessment specifications, expert strategies were developed to facilitate the comparison of the importance of various water quality indicators: Water quality risks are classified into levels based on health status, as shown in Table 3. Table 4 shows the importance scores of 1-9 for each level in Table 3.

[0034] Table 3 Health Level Classification Standards Table 4 Expert Scoring Sheet for Health Level Importance Water quality risks are classified into levels based on sensory perception, as shown in Table 5. The importance of each level in Table 5 is assigned a score from 1 to 5 (the AHP analytic hierarchy process does not strictly require scores from 1 to 9, but rather scores are based on relative importance), as shown in Table 6.

[0035] Table 5 Sensory Level Classification Criteria Table 6 Expert Scoring Sheet for Sensory Importance The various water quality indicators in this embodiment are mapped to the risk levels in Tables 4 and 6, and the importance scores of each water quality indicator are determined according to the importance of the risk level, forming Table 7 below.

[0036] Table 7 Expert Scoring Results for Indicator Importance Based on the importance score table above, a judgment matrix under the health risk criterion / sensory impact criterion can be constructed. : in, For the quantity of water quality indicators, This represents the importance ratio of the i-th water quality indicator to the j-th water quality indicator under the corresponding criteria, and the matrix... The elements in satisfy: , ,and .

[0037] Step S33: Perform column normalization and row average calculation on the judgment matrix under the two criteria to obtain the basic weights of each water quality indicator in the health level and sensory level. Specifically, this includes the following: ① For the judgment matrix Sum the elements of each column and then... Each element in Divide by the sum of the elements in its column to obtain the column normalized matrix. ,and ; ② Calculate the column normalization matrix. The arithmetic mean of each row of elements And obtain the weight matrix. The This represents the basic weight of the i-th water quality indicator under the corresponding criterion; the basic weight under the health risk criterion is expressed as... The basic weights under the sensory risk criterion are expressed as follows: .

[0038] Step S34: Calculate the maximum eigenvalue of each judgment matrix, and calculate the corresponding eigenvalue based on the maximum eigenvalue. , And complete the consistency check ( To ensure that the basic weights are reasonable and effective, specifically: Maximum eigenvalue The calculation formula is: Consistency index ( ) and consistency ratio ( The formula for calculating ) is: Where n is the order of the judgment matrix (n=17 in this embodiment). The random consistency index is shown in Table 8, and the correspondence between the random consistency index and the order of the judgment matrix is ​​shown in Table 8.

[0039] Table 8. Comparison of Random Consistency Indices and Matrix Order When calculated If the consistency is satisfactory, then the judgment matrix is ​​acceptable; otherwise, iterative corrections are needed until the test is passed.

[0040] To overcome the limitations of consistency testing, especially the difficulty in satisfying consistency in high-order matrices and the susceptibility of subjective judgment bias when the number of indicators is large (e.g., n≥10), the following measures are taken to ensure the scientific validity, rationality, and stability of the weight calculation results: 1. Block decomposition and synthesis: The high-order judgment matrix is ​​divided into several low-order sub-matrices according to the criteria / sub-criteria dimensions. Consistency checks are performed on each sub-matrix. After all sub-matrices pass the checks, they are synthesized to obtain the overall weight, which reduces the difficulty of consistency verification of the high-order matrix and ensures the logical consistency of the weight.

[0041] 2. Automatic verification of reciprocity and transitivity: When entering elements of the judgment matrix, the reciprocity constraint is enforced. , This eliminates fundamental logical errors at the source; simultaneously, it employs the "triangular closure" principle of logarithmic fields to verify transitivity, namely: In the formula, Typically, a value of 0.2-0.3 is used. Items that do not meet the constraints are automatically marked as suspicious for manual correction, ensuring the logical consistency of expert judgment.

[0042] 3. Multi-expert judgment fusion: The judgment matrix is ​​constructed by using independent scoring by multiple experts. The judgment results of each expert are fused by geometric mean to offset the subjective bias of a single expert and improve the objectivity and representativeness of the weighted results.

[0043] 4. Iterative Correction and Optimization: For matrices that fail the consistency check, identify the high-bias judgment entries, adjust the judgment values ​​for each entry, and recalculate the consistency ratio until... This completes matrix iterative optimization, ensuring the mathematical validity of weight calculation.

[0044] 5. Sensitivity analysis verification: Perform perturbation tests of ±5%~10% on key judgment values ​​to examine the fluctuation of weight results, verify the stability of the weight system, and ensure that the final weights are not sensitive to small changes in key parameters, and that the results are reliable and reusable.

[0045] Step S35: Multiply the preset weights of the two criteria by the basic weights of each water quality indicator to obtain the comprehensive health weight and comprehensive sensory weight of each water quality indicator. Specifically, the calculation formulas for the comprehensive health weight and comprehensive sensory weight of each water quality indicator are as follows: in, This represents the overall health weight of the i-th water quality indicator. This represents the overall sensory weight of the i-th water quality indicator; The weighting coefficient for the health level. is the weighting coefficient for the sensory level, and Based on the weight ratio of the criterion layer in step S31, it can be obtained that in this embodiment... , .

[0046] To clearly demonstrate the complete calculation process of the basic weights, three typical indicators (Escherichia coli, free chlorine, and color) were selected from 17 water quality indicators. The entire process of judgment matrix construction, basic weight calculation, and consistency verification is explained in detail: ① According to the importance scores provided in Table 7, the importance scores of Escherichia coli, free chlorine and color in the health level are 8, 6 and 1 respectively, and the importance scores in the sensory level are 1, 3 and 5 respectively. Based on the six importance scores, the judgment matrix under the two levels can be obtained, which is presented in tabular form here. See Table 9 and Table 10.

[0047] Table 9. Element Table of Health Level Judgment Matrix Table 10 Element Table of Sensory Level Judgment Matrix Tables 9 and 10 are presented in formula form as follows: Judgment Matrix under Health Level : Judgment Matrix at the Sensory Level : ② After obtaining the judgment matrices for the two levels, sum the results for each column of the judgment matrices. The results are presented in tabular form, see Tables 11 and 12 below: Table 11 Summation of the Health Level Judgment Matrix Table 12 Summation of Sensory Hierarchy Judgment Matrix Divide each element in the judgment matrix by the sum of its column to obtain a column-normalized matrix, and then perform row average calculation: Column normalization matrix under health level : Based on this, according to the row average formula The weight matrix can be obtained. : The basic weights for the health levels of the three water quality indicators are as follows: , , .

[0048] Similarly, the column normalization matrix under the sensory level can be obtained. and weight matrix : Furthermore, the basic weights for the sensory level of the three water quality indicators are as follows: , , .

[0049] ③ Perform a consistency check on the two aforementioned third-order judgment matrices: Under the health level: Therefore, at the health level, consistency indicators Consistency ratio The judgment matrix has satisfactory consistency, and the weighting results are acceptable.

[0050] At the sensory level: Therefore, at the sensory level, the consistency index Consistency ratio The judgment matrix has satisfactory consistency, and the weighting results are acceptable.

[0051] The above only describes the basic weight calculation and consistency verification process obtained after pairwise comparison of the three water quality indicators. Referring to this complete calculation process and the importance scores provided in Table 7, the basic weight results for pairwise comparison of the 17 water quality indicators can be obtained, as shown in Table 13 below: Table 13 Basic weights of 17 water quality indicators The weights of the health risk criteria and sensory impact criteria in the criteria layer (80% and 20%, respectively) are then multiplied by the base weights of each water quality indicator in the two layers to obtain the overall health weight of each water quality indicator. and sensory comprehensive weight As shown in Table 14 below: Table 14. Overall Weights of 17 Water Quality Indicators Step S4: Based on the basic scores and corresponding comprehensive weights of each water quality indicator at the health level and sensory level, the health level score and sensory level score are obtained by weighted summation. A penalty mechanism is then introduced to calculate the final comprehensive water quality safety score. The penalty mechanism sets differentiated penalty coefficients for different risk levels of each water quality indicator. The final comprehensive water quality safety score formula is as follows: in, Rate the health level. For the sensory level ratings, both are calculated in the same way and determined using the following formulas: In the formula, At that time, it was at the health level. At the sensory level; The basic score of the i-th water quality indicator at the corresponding level is obtained from step S2; The comprehensive weight of the i-th water quality indicator at the corresponding level is obtained from step S3; The complete formula for the comprehensive water quality safety scoring is as follows: The penalty coefficient for the health level. The penalty coefficient for the sensory level is calculated in the same way and determined by the following formulas: In the formula, The penalty level is determined based on the importance of each water quality indicator; the smaller the number, the more important it is. The value is the penalty level corresponding to the water quality indicator with the highest importance among the exceeding indicators. The specific penalty levels are shown in Table 15.

[0052] Table 15 Penalty Levels for Various Water Quality Indicators In the formula for calculating the penalty coefficient, This is a penalty trigger, with a value of 1 (any single water quality indicator exceeds the standard) or 0 (all water quality indicators meet the standard). That is, when a single water quality indicator fails to meet the standard, the score for that level needs to be multiplied by the penalty coefficient. Furthermore, when the penalty coefficient... When the penalty trigger is 1, the penalty coefficient is... That is, if any single indicator exceeds the national standard requirements, the final score of the mandatory sensory level will be 0.

[0053] Based on the comprehensive weighting of various water quality indicators, the monitoring data of the three water quality indicators provided by the water treatment plant, and the basic score obtained from the monitoring data, we can obtain: ① Under the health level: Since no water quality indicators exceeded the standards, , ; ② At the sensory level: Due to excessive levels of free chlorine and color, The most important indicator is chromaticity. ,but ; The overall water quality safety score is as follows: point.

[0054] Step S5: Output the results. Specifically, the following content will be output through the system interface: Numerical score: The overall water quality safety score in the example is 91.49 (consistent with the example in the original document); Grading: A (≥90 points), B (80-89 points), C (70-79 points), D (<70 points); Visual graphics: Line chart: Shows the rating trend over the past 30 days (e.g., rating changes from May 1st to 10th); Bar chart: Comparison of the percentage of health level score (79.82 points) and sensory level score (16.67 points); Highlighted: Free chlorine (0.31 mg / L, internal control standard 0.4-1.0 mg / L) and color (12 degrees, internal control standard ≤10 degrees) are indicators that need to be monitored for exceeding the standard.

[0055] The results are simultaneously pushed to water treatment plant managers (through the company's OA system) and public platforms (such as WeChat mini-programs), supporting water quality transparency queries and risk warnings.

[0056] The above steps are implemented based on the following system, including: The data acquisition module is used to collect monitoring data for various water quality indicators; The indicator judgment module is used to determine the compliance of various water quality indicators based on the monitoring data, and to calculate the basic scores of each water quality indicator at the health level and sensory level using a nonlinear formula. The weight calculation module uses an improved AHP (Analytical Hierarchical Method) to determine the overall health weight and overall sensory weight of each water quality indicator. The scoring calculation module is used to calculate the health level score and sensory level score by weighted summation based on the basic scores and corresponding comprehensive weights of various water quality indicators at the health level and sensory level, and introduces a penalty mechanism to calculate the final comprehensive water quality safety score. The results output module outputs the scoring results as numerical values, grades, and visual graphs.

[0057] In summary, this application clarifies the classification of indicators, standard limits, weights, and penalty levels, quantifies the calculation process using formulas (score calculation, penalty coefficient), and verifies the feasibility of the technical solution by combining actual monitoring data, thus realizing intelligent quantitative assessment and risk warning of drinking water safety quality.

[0058] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method of scoring the safety quality of drinking water, characterized in that, Includes the following steps: Step S1: Construct a multi-level evaluation index system, which includes microbial safety indicators, physicochemical safety indicators and sensory characteristics indicators, and collect monitoring data of various water quality indicators; Step S2: Based on the monitoring data, determine whether each water quality indicator meets the standards, and use a nonlinear formula to calculate the basic scores of each water quality indicator at the health level and sensory level; Step S3: Use the improved AHP (Analytical Hierarchical Analysis) method to determine the overall health weight and overall sensory weight of each water quality indicator; Step S4: Based on the basic scores and corresponding comprehensive weights of each water quality indicator at the health level and sensory level, the health level score and sensory level score are obtained by weighted summation, and a penalty mechanism is introduced to calculate the final comprehensive water quality safety score.

2. The method according to claim 1, characterized in that, The microbiological safety indicators include Escherichia coli, total coliforms, thermotolerant coliforms, and total colony count. The physicochemical safety indicators include free chlorine, total chlorine, nitrite nitrogen, aluminum, manganese, iron, permanganate index, and ammonia nitrogen. The sensory indicators include turbidity, color, odor and taste, visible matter, and pH value.

3. The method according to claim 1, characterized in that, Baseline scores of various water quality indicators under the health level / sensory level Determined by the following nonlinear formula: in, This is the basic score of the i-th water quality indicator at the corresponding level. , where i is the water quality index number. At that time, it was at the health level. At the sensory level, and , , All values ​​are for the corresponding water quality indicators and at the corresponding levels. This is an indicator function that takes the value 1 if the condition is true, and 0 otherwise. These are the measured values ​​of the current water quality indicators. The limit ranges for this water quality indicator are defined in accordance with the "Standards for Drinking Water Quality" (GB 5749-2022) for the health level and in accordance with the internal control standards for water quality at the effluent level for the sensory level. The standard deviation is, and In the formula * Used to prevent calculation errors where the denominator is zero; This indicates the standard limit value corresponding to the water quality indicator, based on the measured value. and the limit range The relative position is selected based on the closest limit value.

4. The method according to claim 1, characterized in that, The improved AHP (Analytic Hierarchy Process) includes the following steps: Step S31: Construct a three-level structure model that includes a target layer, a criterion layer, and a scheme layer. The target layer is the comprehensive score of drinking water safety and quality, the criterion layer includes health risk criteria and sensory impact criteria, and the scheme layer consists of various specific water quality indicators. Step S32: Determine the importance scores of each water quality indicator under the two criteria of health risk and sensory impact based on expert scores, and construct a pairwise comparison judgment matrix using the 1-9 scale method; Step S33: Perform column normalization and row average calculation on the judgment matrix under the two criteria to obtain the basic weights of each water quality indicator in the health level and sensory level; Step S34: Calculate the maximum eigenvalue of each judgment matrix, and calculate the corresponding eigenvalue based on the maximum eigenvalue. , And complete the consistency check ( ), ensuring that the basic weights are reasonable and effective; Step S35: Multiply the preset weights of the two criteria with the basic weights of each water quality indicator to obtain the comprehensive health weight and comprehensive sensory weight of each water quality indicator.

5. The method according to claim 4, characterized in that, Step S32 determines the importance score of each water quality indicator, including: Based on the "Standards for Drinking Water Quality" (GB 5749-2022) and the drinking water safety assessment specifications, each water quality indicator was classified and its importance was determined at two levels: health risk and sensory impact. Based on the importance of each level, a 1-9 scale was used to assign importance scores to the health level and sensory level, respectively, which served as the basis for the weight calculation of the analytic hierarchy process.

6. The method according to claim 4, characterized in that, The judgment matrix under the health risk criterion / sensory impact criterion in step S32 Defined by the following expression: in, For the quantity of water quality indicators, This represents the importance ratio of the i-th water quality indicator to the j-th water quality indicator under the corresponding criteria, and the matrix... The elements in the set satisfy: , ,and ; Step S33 specifically includes: For the judgment matrix Sum the elements of each column and then... Each element in Divide by the sum of the elements in its column to obtain the column normalized matrix. ,and ; Calculate the column normalized matrix The arithmetic mean of each row of elements And obtain the weight matrix. The This represents the basic weight of the i-th water quality indicator under the corresponding criterion, and the basic weight under the health risk criterion is expressed as... The basic weights under the sensory risk criterion are expressed as follows: ; In step S35, the specific calculation formulas for the comprehensive health weight and comprehensive sensory weight of each water quality indicator are as follows: in, This represents the overall health weight of the i-th water quality indicator. This represents the overall sensory weight of the i-th water quality indicator; The weighting coefficient for the health level. is the weighting coefficient for the sensory level, and .

7. The method according to claim 1, characterized in that, The penalty mechanism sets differentiated penalty coefficients for different risk levels of various water quality indicators, and the final comprehensive water quality safety score formula is as follows: in, Rate the health level. For the sensory level ratings, both are calculated in the same way and determined using the following formulas: In the formula, At that time, it was at the health level. At the sensory level; The basic score of the i-th water quality indicator at the corresponding level is obtained from step S2; The comprehensive weight of the i-th water quality indicator at the corresponding level is obtained from step S3; The penalty coefficient for the health level. The penalty coefficient for the sensory level is calculated in the same way and determined by the following formulas: In the formula, The penalty level is determined based on the importance of each water quality indicator; the smaller the number, the more important it is. The value is the penalty level corresponding to the water quality indicator with the highest importance among the exceeding indicators; The penalty is triggered by a value of 1 (any single water quality indicator exceeds the standard) or 0 (all water quality indicators meet the standard).

8. The method according to claim 7, characterized in that, In the aforementioned penalty mechanism, when the penalty coefficient... When triggered, penalty coefficient .

9. A drinking water safety quality scoring system, characterized in that, include: The data acquisition module is used to collect monitoring data for various water quality indicators; The indicator judgment module is used to determine the compliance of various water quality indicators based on the monitoring data, and to calculate the basic scores of each water quality indicator at the health level and sensory level using a nonlinear formula. The weight calculation module uses an improved AHP (Analytical Hierarchical Method) to determine the overall health weight and overall sensory weight of each water quality indicator. The scoring calculation module is used to calculate the health level score and sensory level score by weighted summation based on the basic scores and corresponding comprehensive weights of various water quality indicators at the health level and sensory level, and introduces a penalty mechanism to calculate the final comprehensive water quality safety score. The results output module outputs the scoring results as numerical values, grades, and visual graphs.

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