Hydrological element non-stationary sequence division method, system and equipment and storage medium

Abstract

The embodiment of the invention provides a hydrological element non-stationary sequence division method, system and device and a storage medium, and belongs to the technical field of data processing. The method comprises the steps of firstly obtaining a first sequence about annual hydrological element indexes, then constructing a plurality of first sample sequences with continuous time according to the first sequence, and performing data distribution consistency check between the two first sample sequences to determine a plurality of first subsequences with hydrological elements stably distributed in the first sequence; obtaining day-degree hydrological element index values of all dates in an inter-annual period corresponding to the first sub-sequence to construct a second sequence, constructing a plurality of second sample sequences with continuous time according to the second sequence, and performing consistency check between the second sample sequences and the target distribution function, and determining a plurality of second subsequences in which the hydrological elements are stably distributed in the second sequence. According to the method, inter-year and intra-year dual-scale division is realized, and the reliability of hydrological element non-stationary sequence division can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of data processing, and particularly relates to a method, a system, a device and a storage medium for dividing non-stationary sequences of hydrological elements. Background Art

[0002] Affected by the changing environment, the hydrological situation of the basin, the underlying surface conditions and the runoff generation and concentration mechanism have changed. The superposition results in the time series of hydrological elements such as rainfall and runoff showing non-stationary and non-linear characteristics. Dividing the non-stationary time series of hydrological elements into multiple subsequences with good consistency is one of the effective ways to require the samples to obey the assumption of "independent and identically distributed" for the model to adapt to the changing environment and fully apply and mine the information of measured data. That is, by dividing the non-stationary time series of hydrological elements into stationary sequences, it helps researchers to study the regularity of hydrological conditions. In related technologies, the method for dividing non-stationary time series of hydrological elements is usually based on the division of the annual flood season (pre-flood season, main flood season and post-flood season), without considering the impact of long-term climate change on the annual flood season, resulting in low reliability of the division of non-stationary sequences of hydrological elements, thus affecting the study of the regularity of hydrological conditions. Summary of the Invention

[0003] The main purpose of the embodiments of the present application is to propose a method, a system, a device and a storage medium for dividing non-stationary sequences of hydrological elements, aiming to improve the reliability of dividing non-stationary sequences of hydrological elements.

[0004] To achieve the above object, on the one hand, an embodiment of the present application proposes a method for dividing non-stationary sequences of hydrological elements, including:

[0005] Obtaining a first sequence, where the first sequence includes multiple annual hydrological element index values arranged in chronological order;

[0006] Constructing multiple first sample sequences with continuous time according to the first sequence, and performing a data distribution consistency test between two first sample sequences to determine multiple first subsequences with stationary distribution of hydrological elements in the first sequence;

[0007] Obtaining the daily hydrological element index values of each date in the inter-annual cycle corresponding to the first subsequence, and constructing a second sequence according to the daily hydrological element index values of each date;

[0008] Constructing multiple second sample sequences with continuous time according to the second sequence, and performing a consistency test between the second sample sequence and a target distribution function to determine multiple second subsequences with stationary distribution of hydrological elements in the second sequence.

[0009] In some embodiments, the constructing multiple first sample sequences with continuous time according to the first sequence includes the following steps:

[0010] Determine a plurality of candidate division numbers according to the data numbers of the first sequence;

[0011] According to each candidate division number, intercept and divide the first sequence to obtain a plurality of sample sequence pairs corresponding to each candidate division number, wherein each sample sequence pair includes two first sample sequences.

[0012] In some embodiments, according to each candidate division number, intercepting and splitting the first sequence to obtain a plurality of sample sequence pairs corresponding to each candidate division number includes the following steps:

[0013] Initialize the starting number as the number of the first data in the first sequence, and initialize the ending number as the candidate division number plus 2;

[0014] Execute the first step, wherein the first step includes intercepting and dividing the first sequence according to the starting number, the candidate division number, and the ending number to obtain a corresponding sample sequence pair;

[0015] Execute the second step, wherein the second step includes updating the ending number to the current ending number plus 1, and repeating the execution of the first step until the ending number is updated to the number of the last data in the first sequence and the first step is executed;

[0016] Update the starting number to the current starting number plus 1, and update the ending number to the candidate division number plus 2, and repeat the execution of the first step to the second step until the starting number is updated to one less than the candidate division number and the first step and the second step are executed.

[0017] In some embodiments, performing a data distribution consistency test between two first sample sequences to determine a plurality of first subsequences with a stable distribution of hydrological elements in the first sequence includes the following steps:

[0018] Calculate the degree of difference between the data samples of the two first sample sequences in each sample sequence pair to obtain a consistency test set;

[0019] Select from the consistency test set the sample sequence pairs with the degree of difference between the data samples less than a first preset value, and obtain a set of division numbers according to the division point descriptions corresponding to the selected sample sequence pairs, wherein the division point descriptions include the starting number, the candidate division number, and the ending number;

[0020] Divide the first sequence according to the set of division numbers to obtain a plurality of second subsequences.

[0021] In some embodiments, partitioning the first sequence according to the set of partitioning serial numbers to obtain a plurality of second subsequences includes the following steps:

[0022] Determine a plurality of different partitioning schemes for the complete and continuous partitioning of the first sequence according to the description of each partitioning point in the set of partitioning serial numbers;

[0023] Partition the first sequence according to each partitioning scheme, and calculate the sum of the data sample difference degrees between the subsequences after partitioning;

[0024] Take the partitioning scheme corresponding to the minimum sum of the data sample difference degrees as the target partitioning scheme;

[0025] Partition the first sequence according to the target partitioning scheme to obtain a plurality of second subsequences.

[0026] In some embodiments, obtaining the daily hydrological element index values of each date in the interannual cycle corresponding to the first subsequence, and constructing a second sequence according to the daily hydrological element index values of each date includes the following steps:

[0027] Obtain the daily hydrological element index data sets of each year in the interannual cycle corresponding to the first subsequence;

[0028] Extract the daily hydrological element index value of the target date from the daily hydrological element index data sets of each year, and take the average value of the daily hydrological element index values extracted from each year as the daily hydrological element index value of the target date;

[0029] Construct a second sequence according to the daily hydrological element index values of different target dates.

[0030] In some embodiments, constructing a plurality of second sample sequences that are continuous in time according to the second sequence, and performing a consistency test between the second sample sequences and the target distribution function to determine a plurality of second subsequences with a stable distribution of hydrological elements in the second sequence includes the following steps:

[0031] Initialize the first partitioning serial number as the serial number of the first data in the second sequence;

[0032] Execute the third step, where the third step includes partitioning the second sequence starting from the first partitioning serial number and in sequence lengths to obtain corresponding second sample sequences, calculating the data distribution difference degree between the second sample sequences and the target distribution function; screening out the second sample sequences with a data distribution difference degree less than the second preset value, and determining the target partitioning point of the second sequence according to the end point of the second sample sequence with the largest sequence length screened out.

[0033] Update the first division serial number to the target division point, and repeatedly execute the third step until the first division serial number is updated to the serial number of the last data in the second sequence;

[0034] Divide the second sequence according to the multiple target division points to obtain multiple second subsequences.

[0035] To achieve the above object, another aspect of the embodiments of the present application provides a system for dividing non-stationary sequences of hydrological elements, including:

[0036] A first module, configured to obtain a first sequence, where the first sequence includes multiple annual hydrological element index values arranged in chronological order of years;

[0037] A second module, configured to construct multiple first sample sequences with continuous time according to the first sequence, and perform a data distribution consistency test between two first sample sequences to determine multiple first subsequences with stable distribution of hydrological elements in the first sequence;

[0038] A third module, configured to obtain the daily hydrological element index values of each date in the inter-annual cycle corresponding to the first subsequence, and construct a second sequence according to the daily hydrological element index values of each date;

[0039] A fourth module, configured to construct multiple second sample sequences with continuous time according to the second sequence, and perform a consistency test between the second sample sequence and a target distribution function to determine multiple second subsequences with stable distribution of hydrological elements in the second sequence.

[0040] To achieve the above object, another aspect of the embodiments of the present application provides an electronic device, where the electronic device includes a memory, a processor, a program stored on the memory and executable on the processor, and a data bus for realizing connection communication between the processor and the memory. When the program is executed by the processor, the method described in the above embodiments is implemented.

[0041] To achieve the above object, another aspect of the embodiments of the present application provides a storage medium, where the storage medium is a computer-readable storage medium for computer-readable storage. The storage medium stores one or more programs, and the one or more programs can be executed by one or more processors to implement the method described in the above embodiments.

[0042] The method, system, device and storage medium for dividing non-stationary sequences of hydrological elements proposed in this application first obtain multiple annual hydrological element index values arranged in chronological order, that is, the first sequence. Then, multiple temporally continuous first sample sequences are constructed based on the first sequence, and a data distribution consistency test is performed between two first sample sequences to determine multiple first subsequences with stable distributions of hydrological elements in the first sequence, realizing the stationary division on the interannual scale. Then, the daily hydrological element index values for each date under the interannual cycle corresponding to the first subsequence are obtained, and a second sequence is constructed based on the daily hydrological element index values for each date. Multiple temporally continuous second sample sequences are constructed based on the second sequence, and a consistency test is performed between the second sample sequence and the target distribution function to determine multiple second subsequences with stable distributions of hydrological elements in the second sequence. Based on the stationary division on the interannual scale, this application further divides the non-stationary sequences within the year, considering the impact of long-term climate change on the flood season within the year, and improving the reliability of the division of non-stationary sequences of hydrological elements. Description of the Drawings

[0043] Figure 1 is a flowchart of the method for dividing non-stationary sequences of hydrological elements provided by an embodiment of the present application;

[0044] Figure 2 is a schematic diagram of the first sequence formed by the average annual runoff of a hydrological station provided by an embodiment of the present application;

[0045] Figure 3 is a schematic diagram of the calculation results of the interannual characteristic index sequence p1 starting from different years provided by an embodiment of the present application;

[0046] Figure 4 is a schematic diagram of the second sequence formed by the daily average runoff of a hydrological station under different interannual cycles provided by an embodiment of the present application;

[0047] Figure 5 is a schematic diagram of the hardware structure of the electronic device provided by an embodiment of the present application. Detailed Embodiments

[0048] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0049] It should be noted that although the functional modules are divided in the system and the logical sequence is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order from the module division in the system or the sequence in the flowchart. Terms such as "first" and "second" in the specification, claims, and the above-mentioned drawings are used to distinguish similar objects and do not necessarily describe a specific order or sequence.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0051] First, several terms involved in this application are analyzed:

[0052] The K-S test (Kolmogorov-Smirnov test) is a non-parametric statistical test method used to compare sample data with a reference distribution (one-sample K-S test) or to compare the distributions of two samples (two-sample K-S test). Its core idea is to determine whether a sample comes from a specific distribution or whether two samples come from the same distribution by comparing the maximum difference between the cumulative distribution functions (CDFs). The test statistic of the K-S test is the D value, which represents the maximum vertical distance between two cumulative distribution functions. According to the D value and the sample size, the p value is calculated. Assuming the null hypothesis is that two samples come from the same distribution, if the p value is less than the significance level (such as 0.05), the null hypothesis is rejected; if the p value is greater than the significance level, the null hypothesis cannot be rejected.

[0053] The embodiments of this application provide a method, system, device, and storage medium for dividing non-stationary sequences of hydrological elements, aiming to improve the reliability of dividing non-stationary sequences of hydrological elements.

[0054] The method, system, device, and storage medium for dividing non-stationary sequences of hydrological elements provided by the embodiments of this application are specifically described through the following embodiments. First, the method for dividing non-stationary sequences of hydrological elements in the embodiments of this application is described.

[0055] The method for dividing non-stationary sequences of hydrological elements provided by the embodiments of the present application relates to the technical field of data processing. The method for dividing non-stationary sequences of hydrological elements provided by the embodiments of the present application can be applied to a terminal, or to a server side, or can also be software running on a terminal or a server side. In some embodiments, the terminal can be a smart phone, a tablet computer, a notebook computer, a desktop computer, etc.; the server side can be configured as an independent physical server, or can be configured as a server cluster or a distributed system composed of multiple physical servers, or can also be configured as a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN, and big data and artificial intelligence platforms; the software can be an application for implementing the method for dividing non-stationary sequences of hydrological elements, etc., but is not limited to the above forms.

[0056] The present application can be used in many general or special computer system environments or configurations. For example: personal computers, server computers, handheld or portable devices, tablet devices, multi-processor systems, microprocessor-based systems, set-top boxes, programmable consumer electronic devices, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, and so on. The present application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The present application can also be practiced in a distributed computing environment, where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules can be located in local and remote computer storage media including storage devices.

[0057] Figure 1 is an optional flowchart of the method for dividing non-stationary sequences of hydrological elements provided by the embodiments of the present application, Figure 1 The method in may include but is not limited to steps S101 to S104.

[0058] Step S101, obtain a first sequence, where the first sequence includes multiple annual hydrological element index values arranged in chronological order of years;

[0059] Step S102, construct multiple first sample sequences with continuous time according to the first sequence, and perform a data distribution consistency test between two first sample sequences to determine multiple first subsequences with a stationary distribution of hydrological elements in the first sequence;

[0060] Step S103: Obtain the daily hydrological element index values for each date in the inter-annual cycle corresponding to the first subsequence, and construct a second sequence based on the daily hydrological element index values for each date.

[0061] Step S104: Construct multiple second sample sequences that are continuous in time based on the second sequence, and perform a consistency test between the second sample sequences and the target distribution function to determine multiple second subsequences with a stable distribution of hydrological elements in the second sequence.

[0062] Steps S101 to S104 illustrated in the embodiments of the present application first obtain multiple annual hydrological element index values arranged in chronological order of years, that is, the first sequence, then construct multiple first sample sequences that are continuous in time based on the first sequence, and perform a data distribution consistency test between the two first sample sequences to determine multiple first subsequences with a stable distribution of hydrological elements in the first sequence, realizing the stationarity division on the inter-annual scale. Then, obtain the daily hydrological element index values for each date in the inter-annual cycle corresponding to the first subsequence, construct a second sequence based on the daily hydrological element index values for each date, construct multiple second sample sequences that are continuous in time based on the second sequence, and perform a consistency test between the second sample sequences and the target distribution function to determine multiple second subsequences with a stable distribution of hydrological elements in the second sequence. On the basis of the stationarity division on the inter-annual scale, the present application further divides the non-stationary sequence within the year, considering the influence of long-term climate change on the flood season within the year, and improving the reliability of the division of the non-stationary sequence of hydrological elements.

[0063] In step S101 of some embodiments, the first sequence includes multiple annual hydrological element index values arranged in chronological order of years. The type of hydrological element index can be set according to actual analysis requirements. For example, the type of hydrological element index can be a rainfall index or a runoff index, etc., and the embodiments of the present application do not make specific limitations.

[0064] Furthermore, the purpose of dividing the non-stationary sequence of hydrological elements is to divide the inter-annual cycle and the intra-annual cycle. The embodiments of the present application can select data of an index type that is convenient for analysis as the first sequence to be analyzed.

[0065] Exemplarily, taking preliminary measured runoff and rainfall data as materials, denote the sequence length of the measured runoff data as L Q and the sequence length of the measured rainfall data as L R , with the unit of year, and the selection method is as follows:

[0066] When L Q ≥ the preset data volume (for example, 30), use the runoff data as the subsequent analysis material, that is, form the first sequence with the annual runoff for each year;

[0067] When L QWhen the preset data volume is reached, if L R ≥ the preset data volume, the rainfall data is used as the subsequent analysis data, that is, the annual rainfall of each year forms the first sequence; if L R < the preset data volume, both the runoff data and the rainfall data can be used as the subsequent analysis data, that is, a sequence formed by the annual rainfall of each year is formed and a sequence of the annual runoff of each year These two sequences are respectively used as the first sequence for inter - annual cycle and intra - annual cycle division, and finally the cycle division results based on these two sequences are comprehensively considered.

[0068] In step S102 of some embodiments, the first sequence can be pre - divided into various first sample sequences. The annual hydrological element index values included in the first sample sequence are continuous in time, and different first sample sequences have different lengths, time starting points or time ending points. By performing a data distribution consistency test between every two of all the first sample sequences, two first sample sequences with significantly different data distributions can be determined, indicating that the data distributions within these two first sample sequences may be stable. According to each pair of two first sample sequences with significantly different data distributions, the first sequence with non - stationary hydrological elements can be continuously divided to obtain multiple first sub - sequences with stable hydrological element distributions within the sequence, thereby realizing the division of the inter - annual cycle.

[0069] In this embodiment, the method for testing the data distribution consistency of two first sample sequences can adopt the two - sample K - S test method, Anderson - Darling test method, Epps - Singleton test method or maximum mean difference method, etc.

[0070] In step S103 of some embodiments, each first sub - sequence corresponds to an inter - annual cycle, and the ranges of each inter - annual cycle do not overlap. Obtain the daily hydrological element index values of each date under the inter - annual cycle, and construct a second sequence according to the daily hydrological element index values of each date. Exemplarily, assume that an inter - annual cycle is from 1997 to 2002. Then, the daily hydrological element index values of each date in any one of the years from 1997 to 2002 can be obtained, so as to obtain a second sequence with the date as the time unit. In another example, assume that an inter - annual cycle is from 1997 to 2002. Then, the daily hydrological element index values corresponding to each of these six years from 1997 to 2002 can be obtained. For each date (xx month xx day), the average value of the daily hydrological element index values of this date in the six years can be calculated, and the second sequence is constructed with the average values of each date.

[0071] In step S104 of some embodiments, the second sequence can be pre-divided into various second sample sequences. The daily hydrological element index values included in the second sample sequences are continuous in time, and different second sample sequences are different in length, time starting point or time ending point. By performing a data distribution consistency test on each second sample sequence and the target distribution function respectively, it is possible to determine the second sample sequences that are significantly consistent with the data distribution of the target distribution function, indicating that the data distribution within the second sample sequence conforms to the data distribution of the target distribution function. Based on each second sample sequence that is significantly consistent with the data distribution of the target distribution function, continuous division of the second sequence can be achieved, obtaining multiple second subsequences with a stable distribution of hydrological elements within the sequence, thereby achieving the division of the annual cycle.

[0072] In this embodiment, the target distribution function can be selected according to the regular variation law of the annual cycle of the hydrological element index. The target distribution function can adopt the Poisson distribution function. The Poisson distribution curve is a graphical representation of the Poisson distribution probability mass function (PMF) or cumulative distribution function (CDF). The Poisson distribution is a discrete probability distribution used to describe the probability distribution of the number of occurrences of an event within a fixed time or space. It is applicable to situations where the probability of the event occurring is low and independent.

[0073] In this embodiment, the method for testing the data distribution consistency between the second sample sequence and the Poisson distribution function can adopt the two-sample K-S test method, Anderson-Darling test method, Epps-Singleton test method or maximum mean discrepancy method, etc.

[0074] According to some embodiments of the present application, in step S102, the step of constructing multiple first sample sequences with continuous time according to the first sequence may include, but is not limited to, the following steps:

[0075] Step S201: Determine multiple candidate division numbers according to the data numbers of the first sequence;

[0076] Step S202: According to each candidate division number, intercept and divide the first sequence to obtain multiple sample sequence pairs corresponding to each candidate division number, where each sample sequence pair includes two first sample sequences.

[0077] In this embodiment, the corresponding candidate partition numbers are determined according to the data numbers of the first sequence. Exemplarily, assume that the first sequence is {40, 34, 23, 31, 24}, then the candidate partition numbers are 0, 1, 2, 3, 4 respectively. For each candidate partition number, at least one data before and including the candidate partition number in the first sequence can be taken to form a first sample sequence, and at least one data after the candidate partition number in the first sequence can be taken to form a first sample sequence. Exemplarily, for the candidate partition number "2", taking 1 data before and including the serial number 2 in the first sequence gives the first sample sequence {23}, taking 2 data before and including the serial number 2 in the first sequence gives the first sample sequence {34, 23}, taking 3 data before and including the serial number 2 in the first sequence gives the first sample sequence {40, 34, 23}, taking 1 data after the serial number 2 in the first sequence gives the first sample sequence {31}, and so on, so as to obtain multiple sample sequence pairs corresponding to each candidate partition number.

[0078] According to some embodiments of the present application, in step S202, the step of intercepting and splitting the first sequence according to each candidate partition number to obtain multiple sample sequence pairs corresponding to each candidate partition number may include but is not limited to the following steps:

[0079] Step S301, initialize the starting serial number as the serial number of the first data in the first sequence, and initialize the ending serial number as the candidate partition number plus 2;

[0080] Step S302, execute the first step, where the first step includes intercepting and partitioning the first sequence according to the starting serial number, the candidate partition number, and the ending serial number to obtain the corresponding sample sequence pair;

[0081] Step S303, execute the second step, where the second step includes updating the ending serial number to the current ending serial number plus 1, and repeating the execution of the first step until the ending serial number is updated to the serial number of the last data in the first sequence and the first step is executed;

[0082] Step S304, update the starting serial number to the current starting serial number plus 1, and update the ending serial number to the candidate partition number plus 2, and repeat the execution of the first step to the second step until the starting serial number is updated to the candidate partition number minus 1 and the first step and the second step are executed.

[0083] In this embodiment, let the number of the first data in the first sequence be 0. For each candidate partition sequence, that is, the year to be analyzed n (n = 1, 2,..., N), the extraction method of its first sample sequence is as follows:

[0084] S11. Initialize the starting serial number x = 0 (i.e., the serial number of the first data in the first sequence), and initialize the ending serial number y = n + 2;

[0085] S12. Extract the data with the first serial number from serial number x to n, and extract the data from n + 1 to y in the first sequence to obtain two corresponding first sample sequences, and these two first sample sequences form a sample sequence pair;

[0086] S13. Let y = y + 1, and repeat step S12 until step S12 with the condition y = N is completed, then jump out of the loop and execute step S14; in the above steps S11 to S13, it realizes extracting the sequences from x to n in the first sequence respectively and the sequences from n + 1 to n + 2, n + 3,..., N in sequence, and correspondingly obtaining sample sequence pairs;

[0087] S14. Let x = x + 1, and y = n + 2, then repeat the above steps S12 to S13 until step S14 with the condition x = n - 1 is completed, end the current process, and traverse to obtain multiple sample sequence pairs of candidate division serial numbers; in step S14, it realizes shortening the distance between the starting serial number and n by a step of 1, that is, successively extracting the sequences from 1, 2,..., n - 1 to n in the first sequence respectively and the sequences from n + 1 to n + 2, n + 3,..., N in sequence until n = N - 1, and correspondingly obtaining sample sequence pairs.

[0088] In the above traversal process, the first sequence is divided into two front and back samples with n as the boundary, and the annual hydrological element index value corresponding to n is classified into the previous sample.

[0089] According to some embodiments of the present application, in step S102, the steps of performing a data distribution consistency test between two first sample sequences to determine multiple first subsequences with a stable distribution of hydrological elements in the first sequence may include but are not limited to the following steps:

[0090] Step S401. Calculate the data sample difference degree between the two first sample sequences in each sample sequence pair to obtain a consistency test set;

[0091] Step S402. Screen out the sample sequence pairs with the data sample difference degree less than the first preset value from the consistency test set, and obtain a division serial number set according to the division point descriptions corresponding to the screened sample sequence pairs, where the division point descriptions include the starting serial number, the candidate division serial number, and the ending serial number;

[0092] Step S403. Divide the first sequence according to the division serial number set to obtain multiple second subsequences.

[0093] In this embodiment, the two-sample K-S test method can be used to perform a consistency test on the data distributions of the two first sample sequences in the sample sequence pair. The sample consistency can be measured by the degree of difference between data samples, that is, the asymptotic significance (two-tailed, denoted as p1) between the two samples can be calculated. By calculating the p1 value of each sample sequence pair, a consistency test set S1{p1} is formed.

[0094] Filter out the sample sequence pairs with p1 less than the first preset value (for example, p1≤0.01) from the consistency test set. The sample sequence pairs with p1≤0.01 indicate that the corresponding two samples have a large difference and may belong to different interannual cycles. According to the division point descriptions (the division point descriptions include the starting serial number, the candidate division serial number, and the ending serial number) corresponding to all the filtered sample sequence pairs, a division serial number set is obtained. Through the division point descriptions in the division serial number set, a continuous division scheme from n = 0 to n = N in the first division can be determined, and thus M first subsequences TS m (m = 1, 2,..., M).

[0095] According to some embodiments of the present application, in step S403, the step of dividing the first sequence according to the division serial number set to obtain a plurality of second subsequences may include, but is not limited to, the following steps:

[0096] Step S501: Determine a plurality of different division schemes for the complete continuous division of the first sequence according to each division point description in the division serial number set;

[0097] Step S502: Divide the first sequence according to each division scheme and calculate the sum of the data sample difference degrees between the divided subsequences;

[0098] Step S503: Use the division scheme corresponding to the sum of the data sample difference degrees as the target division scheme;

[0099] Step S504: Divide the first sequence according to the target division scheme to obtain a plurality of second subsequences.

[0100] In this embodiment, multiple different continuous partitioning schemes may be described by dividing each partitioning point in the sequence number set. Exemplarily, assuming that the time period of the first sequence is from 1962 to 2024, through the process of the above embodiment, the corresponding partitioning time periods for all partitioning point descriptions in the sequence number set that may be obtained are 1962 - 1994, 1995 - 1996, 1997 - 2000, 1988 - 1996, 2001 - 2024, 1962 - 1987, 1997 - 2003, 2004 - 2024. Taking the principle of complete continuous partitioning of the first sequence, the above partitioning time periods can be combined to obtain Partitioning Scheme 1 as 1962 - 1994, 1995 - 1996, 1997 - 2000, 2001 - 2024, and Partitioning Scheme 2 as 1962 - 1987, 1988 - 1996, 1997 - 2003, 2004 - 2024.

[0101] Partition the first sequence according to each partitioning scheme and calculate the sum of the data sample difference degrees between the subsequences after partitioning, that is, calculate p1 between every two of the first sample sequences corresponding to each partitioning time period in the partitioning scheme, and then calculate the sum of each p1. Take the partitioning scheme corresponding to the sum of p1 as the target partitioning scheme, and use the target partitioning scheme to partition the first sequence to obtain multiple second subsequences. The embodiment of the present application selects the partitioning scheme corresponding to the sum of p1 as the target partitioning scheme, which can maximize the difference degree between the first subsequences and improve the rationality of inter - annual partitioning.

[0102] Further, a partitioning scheme with the largest number of partitioning time periods and the smallest possible sum of p1 can be selected as the target partitioning scheme, which can improve the fineness of inter - annual cycle partitioning while improving the rationality of inter - annual partitioning.

[0103] According to some embodiments of the present application, in step S103, the steps of obtaining the daily hydrological element index values for each date under the inter - annual cycle corresponding to the first subsequence and constructing the second sequence according to the daily hydrological element index values for each date may include, but are not limited to, the following steps:

[0104] Step S601, obtain the daily hydrological element index data sets for each year in the inter - annual cycle corresponding to the first subsequence;

[0105] Step S602, extract the daily hydrological element index value of the target date from the daily hydrological element index data sets for each year, and take the average value of the daily hydrological element index values from each year as the daily hydrological element index value of the target date;

[0106] Step S603, construct the second sequence according to the daily hydrological element index values of different target dates.

[0107] In this embodiment, the second sequence includes the daily hydrological element index values for each date in a year. Taking January 1st as an example, the calculation process of the corresponding daily hydrological element index value (such as the daily average rainfall) in the second sequence with an inter-annual cycle from 1999 to 2002 is as follows: Obtain the rainfall on January 1st, 1999, the rainfall on January 1st, 2000, the rainfall on January 1st, 2001, and the rainfall on January 1st, 2002, and calculate the average value of the above four rainfall amounts to obtain the daily average rainfall on January 1st in the second sequence.

[0108] According to some embodiments of the present application, in step S104, the steps of constructing a plurality of second sample sequences with continuous time from the second sequence and performing a consistency test between the second sample sequences and the target distribution function to determine a plurality of second subsequences of the stationary distribution of hydrological elements in the second sequence may include, but are not limited to, the following steps:

[0109] Step S701, initialize the first division serial number as the serial number of the first data in the second sequence;

[0110] Step S702, execute the third step, where the third step includes dividing the second sequence in turn with the first division serial number as the starting point and according to different sequence lengths to obtain the corresponding plurality of second sample sequences, calculating the data distribution difference degree between the second sample sequences and the target distribution function; screening out the second sample sequences with the data distribution difference degree less than the second preset value, and determining the target division point of the second sequence according to the end point of the second sample sequence with the largest sequence length selected;

[0111] Step S703, update the first division serial number to the target division point, and repeat the execution of the third step until the first division serial number is updated to the serial number of the last data in the second sequence;

[0112] Step S704, divide the second sequence according to a plurality of target division points to obtain a plurality of second subsequences.

[0113] In this embodiment, let the starting date serial number in the second sequence be 0, and divide the second sample data with the serial number of the date to be analyzed as x (x = 1, 2,..., X). Use the one-parameter K-S test to calculate the data distribution difference degree between each second sample sequence and the Poisson distribution (i.e., the target distribution function), that is, the asymptotic significance (two-tailed, denoted as p2). The calculation process is as follows:

[0114] Extract a plurality of second sample sequences from the second sequence from the first division serial number (initialized as the starting date serial number) to x (x = 1, 2,..., X) in turn, and calculate the p2 values of each second sample sequence and the Poisson distribution respectively;

[0115] Select the x corresponding to the second sample sequence with a p2 value greater than the second preset value (e.g., p2≥0.05), and record the serial number corresponding to the largest x as Y1;

[0116] Update the first division serial number to Y1 + 1, sequentially extract the p2 values of multiple second sample sequences from Y1 + 1 to Y1 + 2, Y1 + 3,..., X, calculate the p2 values of each second sample sequence and the Poisson distribution respectively, select the termination dates corresponding to the second sample sequences with p2 values greater than the second preset value (e.g., p2≥0.05), and record the serial number corresponding to the largest termination date as Y2;

[0117] Update the first division serial number to Y2 + 1, sequentially extract the p2 values of multiple second sample sequences from Y2 + 1 to Y2 + 2, Y3 + 3,..., X, calculate the p2 values of each second sample sequence and the Poisson distribution respectively, select the termination dates corresponding to the second sample sequences with p2 values greater than the second preset value (e.g., p2≥0.05), and record the serial number corresponding to the largest termination date as Y3;

[0118] And so on, until the first division serial number is updated to the serial number of the last data of the second sequence, and the in - year dynamic division set is obtained. Among them, the in - year dynamic division set has multiple target division points, and each target division point is the serial number Y1, Y2, Y3,... corresponding to the largest termination date obtained in each step of the above process. According to the multiple target division points Y x The second sequence is divided into multiple second subsequences, thereby corresponding to obtaining multiple in - year cycles, that is, using Y x as the boundary to divide the second sequence into two front - and - back samples, and the daily hydrological element index values corresponding to Y x are classified into the previous sample.

[0119] According to some embodiments of the present application, only taking the runoff or rainfall index type as the analysis data, the inter - annual cycle is divided according to the first sequence TS of either the annual runoff or the annual rainfall data m Correspondingly, the in - year cycle is divided according to the second sequence of the daily runoff or daily rainfall data Divided.

[0120] If both the runoff data and the rainfall index type are used as the analysis data, the final year - end cycle can be determined by integrating the division results of the inter - annual cycles corresponding to the first sequences of the two kinds of data, and the final in - year cycle can be determined by integrating the division results of the in - year cycles corresponding to the second sequences of the two kinds of data. Exemplarily, the inter - annual cycle TS of the runoff m ={1951, 1960, 1976, 1998, 2013}, and the inter - annual cycle TS of the rainfall m ={1951, 1959, 1981, 1998, 2012}; After merging and removing duplicates for the two, we get: TSm = {1951, 1959, 1960, 1976, 1981, 1998, 2012, 2013}; Delete the rainfall division nodes that appear within the range of ±1 of the runoff data division nodes to obtain TS m = {1951, 1960, 1976, 1981, 1998, 2013}, and use this as the interannual cycle division nodes.

[0121] Next, taking the measured runoff data of a hydrological station on a certain river from 1950 to 2021 as an example, the calculation process of the method proposed in the embodiment of the present application is described.

[0122] First, data selection. The length of the measured runoff data of the hydrological station from 1950 to 2021 is L Q = 72 > 30, and dynamic division is carried out with the runoff data as the data.

[0123] Second, calculate the first sequence of interannual characteristic indicators (i.e., annual hydrological element indicator values), that is, calculate the first sequence of the annual average runoff of the hydrological station The first sequence is as Figure 2 shown.

[0124] Third, interannual scale consistency test:

[0125] Use the two-sample K-S test to traverse the years n to be analyzed and calculate p1. The p1 calculation results of the interannual characteristic indicator sequence (i.e., the first sample sequence) starting from 1950, 1998, and 2002 are as Figure 3 shown.

[0126] Fourth, interannual cycle division:

[0127] After screening, the scheme that satisfies p1 ≤ 0.01 and can achieve continuous division from the starting point to the ending point of the interannual characteristic indicator sequence is shown in Table 1 for continuous division.

[0128] Table 1 Interannual cycle division scheme

[0129]

[0130] As can be seen from Table 1, Scheme 1 is the interannual cycle division scheme that meets the requirements. The 1950 - 2021 runoff sequence is divided into three first subsequences: TS1 = 1950 - 1998, TS2 = 1999 - 2002, and TS3 = 2003 - 2021.

[0131] Fifth, calculate the within-year characteristic indicators: Calculate the within-year characteristic indicator values (i.e., daily hydrological element indicator values) of TS1, TS2, and TS3 respectively to obtain the corresponding second sequence as Figure 4 shown.

[0132] Sixth, dynamic division within a year:

[0133] Use the one-parameter K-S test to traverse the dates x to be analyzed in TS1, TS2, and TS3 to calculate p2. After screening, the results of dynamic division within a year are shown in Table 2.

[0134] Table 2 Annual cycle division scheme

[0135]

[0136] Seventh, dual-scale dynamic division between years and within a year:

[0137] The runoff sequence of the hydrological station from 1950 to 2021 contains three inter-annual cycles. The subsequence from 1950 to 1998 has 9 sub-periods within a year, the subsequence from 1999 to 2002 has 11 sub-periods within a year, and the subsequence from 2003 to 2021 has 8 sub-periods within a year. In practical applications, the inter-annual cycle of the incoming water can be judged based on the characteristic parameters of the reservoir inflow flood forecast, and then the measured data can be used and mined according to the corresponding within-year division scheme.

[0138] This application embodiment also proposes a system for dividing non-stationary sequences of hydrological elements, including:

[0139] The first module is used to obtain a first sequence, where the first sequence includes multiple annual hydrological element index values arranged in chronological order of years;

[0140] The second module is used to construct multiple first sample sequences with continuous time based on the first sequence, and perform a data distribution consistency test between two first sample sequences to determine multiple first subsequences with stable distribution of hydrological elements in the first sequence;

[0141] The third module is used to obtain the daily hydrological element index values of each date under the inter-annual cycle corresponding to the first subsequence, and construct a second sequence based on the daily hydrological element index values of each date;

[0142] The fourth module is used to construct multiple second sample sequences with continuous time based on the second sequence, and perform a consistency test between the second sample sequence and the target distribution function to determine multiple second subsequences with stable distribution of hydrological elements in the second sequence.

[0143] It can be understood that the content in the above embodiments of the method for dividing non-stationary sequences of hydrological elements is applicable to the embodiments of this system. The functions specifically implemented by the embodiments of this system are the same as those of the above embodiments of the method for dividing non-stationary sequences of hydrological elements, and the beneficial effects achieved are also the same as those of the above embodiments of the method for dividing non-stationary sequences of hydrological elements.

[0144] An embodiment of the present application further provides an electronic device, which includes: a memory, a processor, a program stored on the memory and executable on the processor, and a data bus for implementing connection communication between the processor and the memory. When the program is executed by the processor, the above-mentioned method for dividing the non-stationary sequence of hydrological elements is implemented. The electronic device can be any intelligent terminal including a tablet computer, an in-vehicle computer, etc.

[0145] Please refer to Figure 5 , Figure 5 which schematically shows the hardware structure of an electronic device according to another embodiment. The electronic device includes:

[0146] A processor 501, which can be implemented in ways such as a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided by the embodiments of the present application;

[0147] A memory 502, which can be implemented in forms such as a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM). The memory 502 can store an operating system and other application programs. When implementing the technical solutions provided by the embodiments of this specification through software or firmware, the relevant program codes are stored in the memory 502 and are called by the processor 501 to execute the method for dividing the non-stationary sequence of hydrological elements of the embodiments of the present application;

[0148] An input / output interface 503, which is used to implement information input and output;

[0149] A communication interface 504, which is used to implement communication interaction between this device and other devices, and can implement communication through a wired method (such as USB, network cable, etc.) or through a wireless method (such as mobile network, WIFI, Bluetooth, etc.);

[0150] A bus 505, which transmits information between various components of the device (such as the processor 501, the memory 502, the input / output interface 503, and the communication interface 504);

[0151] Among them, the processor 501, the memory 502, the input / output interface 503, and the communication interface 504 achieve communication connections with each other inside the device through the bus 505.

[0152] The embodiments of the present application also provide a storage medium, which is a computer-readable storage medium for computer-readable storage. The storage medium stores one or more programs, and the one or more programs can be executed by one or more processors to implement the above-mentioned method for dividing the non-stationary sequence of hydrological elements.

[0153] As a non-transitory computer-readable storage medium, the memory can be used to store non-transitory software programs and non-transitory computer-executable programs. In addition, the memory can include high-speed random access memory, and can also include non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some embodiments, the memory may optionally include a memory remotely disposed relative to the processor, and these remote memories can be connected to the processor through a network. Examples of the above networks include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0154] The embodiments described in the embodiments of the present application are for more clearly illustrating the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided by the embodiments of the present application. Those skilled in the art will know that with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of the present application are equally applicable to similar technical problems.

[0155] Those skilled in the art can understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of the present application, and may include more or fewer steps than shown in the figures, or combine certain steps, or different steps.

[0156] The system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, that is, they may be located in one place, or may be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0157] Those of ordinary skill in the art can understand that all or some of the steps in the methods disclosed above, and the functional modules / units in the systems and devices can be implemented as software, firmware, hardware, and appropriate combinations thereof.

[0158] In the description of the present application and the above-mentioned drawings, terms such as "first", "second", "third", "fourth", etc. (if any) are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that comprises a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0159] It should be understood that in the present application, "at least one (item)" means one or more, and "a plurality" means two or more. "And / or" is used to describe the association relationship of associated objects and indicates that three relationships may exist. For example, "A and / or B" may mean: only A exists, only B exists, and both A and B exist at the same time. Among them, A and B can be singular or plural. The character " / " generally means that the associated objects before and after are in an "or" relationship. "At least one (one) of the following" or its similar expressions refer to any combination of these items, including any combination of single items (ones) or plural items (ones). For example, at least one (one) of a, b, or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0160] In several embodiments provided by the present application, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the system embodiments described above are merely illustrative. For example, the above-mentioned division of units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection to each other can be through some interfaces. The indirect coupling or communication connection of systems or units can be in electrical, mechanical, or other forms.

[0161] The units described above as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0162] In addition, in each embodiment of the present application, each functional unit can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0163] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes multiple instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in each embodiment of the present application. The foregoing storage medium includes: various media that can store programs such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs.

[0164] The preferred embodiments of the embodiments of the present application have been described above with reference to the accompanying drawings. However, this does not limit the scope of the rights of the embodiments of the present application. Any modification, equivalent replacement, and improvement made by those skilled in the art without departing from the scope and essence of the embodiments of the present application shall be within the scope of the rights of the embodiments of the present application.

Claims

1. A method for dividing non-stationary sequences of hydrological elements, characterized in that, Including the following steps: Obtain a first sequence, where the first sequence includes multiple annual hydrological element index values arranged in chronological order of years; Construct multiple first sample sequences with continuous time according to the first sequence, and conduct a data distribution consistency test between two first sample sequences to determine multiple first subsequences with stable distribution of hydrological elements in the first sequence; Obtain the daily hydrological element index values of each date under the interannual cycle corresponding to the first subsequence, and construct a second sequence according to the daily hydrological element index values of each date; Construct multiple second sample sequences with continuous time according to the second sequence, and conduct a consistency test between the second sample sequence and the target distribution function to determine multiple second subsequences with stable distribution of hydrological elements in the second sequence.

2. The method for dividing the non-stationary sequence of hydrological elements according to claim 1, wherein The constructing multiple first sample sequences with continuous time according to the first sequence includes the following steps: Determine multiple candidate division serial numbers according to the data serial numbers of the first sequence; According to each candidate division serial number, intercept and divide the first sequence to obtain multiple sample sequence pairs corresponding to each candidate division serial number, where each sample sequence pair includes two first sample sequences.

3. The method for dividing the non-stationary sequence of hydrological elements according to claim 2, characterized in that, The intercepting and dividing the first sequence according to each candidate division serial number to obtain multiple sample sequence pairs corresponding to each candidate division serial number includes the following steps: Initialize the starting serial number as the serial number of the first data in the first sequence, and initialize the ending serial number as the candidate division serial number plus 2; Execute the first step, where the first step includes intercepting and dividing the first sequence according to the starting serial number, the candidate division serial number, and the ending serial number to obtain the corresponding sample sequence pair; Execute the second step, where the second step includes updating the ending serial number to the current ending serial number plus 1, and repeating the execution of the first step until the ending serial number is updated to the serial number of the last data in the first sequence and the first step is executed; Update the starting serial number to the current starting serial number plus 1, and update the ending serial number to the candidate division serial number plus 2, and repeat the execution of the first step to the second step until the starting serial number is updated to the candidate division serial number minus 1 and the first step and the second step are executed.

4. The method for dividing the non-stationary sequence of hydrological elements according to claim 3, characterized in that The conducting a data distribution consistency test between two first sample sequences to determine multiple first subsequences with stable distribution of hydrological elements in the first sequence includes the following steps: Calculate the data sample difference degree between the two first sample sequences in each sample sequence pair to obtain a consistency test set; Screen out the sample sequence pairs with the data sample difference degree less than the first preset value from the consistency test set, and obtain a division serial number set according to the division point descriptions corresponding to the screened sample sequence pairs, where the division point descriptions include the starting serial number, the candidate division serial number, and the ending serial number; Divide the first sequence according to the division serial number set to obtain multiple second subsequences.

5. The method for dividing non-stationary sequences of hydrological elements according to claim 4, wherein Dividing the first sequence according to the set of division serial numbers to obtain a plurality of second subsequences, including the following steps: Determine a plurality of different division schemes for the complete continuous division of the first sequence according to each division point description in the set of division serial numbers; Divide the first sequence according to each division scheme, and calculate the sum of the data sample difference degrees between the subsequences after division; Take the division scheme corresponding to the minimum sum of the data sample difference degrees as the target division scheme; Divide the first sequence according to the target division scheme to obtain a plurality of second subsequences.

6. The method for dividing the non-stationary sequence of hydrological elements according to claim 1, characterized in that, Obtaining the daily hydrological element index values of each date in the interannual cycle corresponding to the first subsequence, and constructing a second sequence according to the daily hydrological element index values of each date, including the following steps: Obtain the daily hydrological element index data sets of each year in the interannual cycle corresponding to the first subsequence; Extract the daily hydrological element index value of the target date from the daily hydrological element index data sets of each year, and take the average value of the daily hydrological element index values extracted from each year as the daily hydrological element index value of the target date; Construct a second sequence according to the daily hydrological element index values of different target dates.

7. The method for dividing non-stationary sequences of hydrological elements according to claim 1, characterized in that Constructing a plurality of second sample sequences that are continuous in time according to the second sequence, and performing a consistency test between the second sample sequences and the target distribution function to determine a plurality of second subsequences with a stable distribution of hydrological elements in the second sequence, including the following steps: Initialize the first division serial number as the serial number of the first data in the second sequence; Execute the third step, where the third step includes dividing the second sequence starting from the first division serial number and in sequence lengths to obtain corresponding second sample sequences, calculating the data distribution difference degree between the second sample sequences and the target distribution function; screening out the second sample sequences with a data distribution difference degree less than the second preset value, and determining the target division point of the second sequence according to the end point of the second sample sequence with the largest sequence length; Update the first division serial number to the target division point, and repeat the execution of the third step until the first division serial number is updated to the serial number of the last data in the second sequence; Divide the second sequence according to a plurality of the target division points to obtain a plurality of second subsequences.

8. A non-stationary sequence division system for hydrological elements, characterized in that, Including: The first module is used to obtain a first sequence, where the first sequence includes a plurality of annual hydrological element index values arranged in chronological order; The second module is used to construct a plurality of first sample sequences that are continuous in time according to the first sequence, and perform a data distribution consistency test between two first sample sequences to determine a plurality of first subsequences with a stable distribution of hydrological elements in the first sequence; The third module is used to obtain the daily hydrological element index values of each date in the interannual cycle corresponding to the first subsequence, and construct a second sequence according to the daily hydrological element index values of each date; The fourth module is configured to construct a plurality of second sample sequences that are temporally continuous according to the second sequence, and perform a consistency test between the second sample sequence and the target distribution function to determine a plurality of second subsequences of the stationary distribution of hydrological elements in the second sequence.

9. An electronic device, characterized in that, The electronic device includes a memory, a processor, a program stored on the memory and executable on the processor, and a data bus for realizing connection communication between the processor and the memory. When the program is executed by the processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A storage medium, the storage medium being a computer-readable storage medium for computer-readable storage, characterized in that, The storage medium stores one or more programs, and the one or more programs can be executed by one or more processors to implement the steps of the method according to any one of claims 1 to 7.

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