Method for realizing reversible conversion between water transport upper boundary variable and unbounded variable and related product

Abstract

The invention provides a method for realizing reversible conversion between a water transport upper boundary variable and an unbounded variable and a related product. The method comprises the following steps: valuing an upper bounded variable; converting the upper bounded variable into an unbounded variable; mathematical transformation of bounded variables and unbounded variables is proved to be reversible; proving that the first-order derivative at the forward transformation segmentation point is continuous; and proving that the first-order derivative at the inverse transformation segmentation point is continuous. The method and the device provided by the invention have the beneficial effects that the conversion from the bounded variable of the water transport upper boundary to the unbounded variable is successfully realized. The conversion can meet the requirements of a part of mathematical assimilation methods and mathematical models for unbounded variables in the water transportation information processing and water transportation variable simulation and prediction processes. According to the method, the basic assumptions of the peripheral nested algorithms are not destroyed, the continuity of the algorithms is ensured, and the introduction of new errors is prevented. From the theoretical level, the assimilation precision of the peripheral nested data and the correction precision of the model correction model are higher, and the algorithm is more stable.

Description

Technical Field

[0001] The present invention belongs to the field of water transportation intelligent construction, and in particular relates to a method and related products for realizing reversible conversion between water transportation upper boundary variables and unbounded variables. Background Art

[0002] In the construction of water transportation intelligence, a series of observable water transportation elements and computable and predictable water transportation variables need to be processed, and data fusion is carried out using technologies such as big data and large models. Among the commonly used technical means is data assimilation, that is, combining observation data with model predictions, using the observation results to correct (or rectify) the prediction results, and obtaining a better result through assimilation on the basis of comprehensively considering observation errors and prediction errors, and continuously updating the model calculation. The water transportation elements (or water transportation variables) involved include unbounded variables, bilateral bounded variables, lower boundary bounded variables, and upper boundary bounded variables. Unbounded variables include: flow velocity (a positive value indicates the same direction as the specified direction, and a negative value indicates the opposite direction to the specified direction), wind speed, etc.; bilateral bounded variables include: water temperature (0 - 100 degrees Celsius), humidity (0 - saturation humidity), lock operating water level (design minimum - design maximum), upstream dam water level of the hub (dead water level - design maximum), etc.; lower boundary bounded variables include: rainfall (greater than or equal to 0), snowfall, water depth, etc.; upper boundary bounded variables include: potential energy difference of the water flow relative to the source (less than or equal to 0), soil water suction (when the soil reaches the saturated state, the soil water suction is 0, and negative numbers are often used to represent soil water suction), etc.

[0003] When carrying out data assimilation or robust correction on the observed values of the above water transportation elements or the calculated values of water transportation variables, mathematical models or signal control algorithms such as Kalman filtering and gradient descent method often need to be introduced. Many of these models (or algorithms) have good natural applicability to unbounded variables, but poor applicability to bounded variables, and the direct application in the observation of water transportation bounded elements or the correction of calculated variables has poor effects. There will be a situation where the calculated result after correction exceeds the limited boundary. The conventional method is to insert intermediate steps in the algorithm to force the corrected result back within the boundary conditions. This will cause the original basic assumptions of the algorithm to be violated and break the continuity of the algorithm, thereby introducing unestimable new errors in the process, resulting in the failure of model deviation correction or the collapse of the algorithm, and ultimately affecting the effect of data assimilation.

[0004] The above problems are most difficult to handle with one-sided bounded variables (i.e., lower-bound bounded variables and upper-bound bounded variables). Taking the upper-bound bounded variable as an example, since the upper-bound bounded variable has only one-sided boundary condition restrictions (i.e., there are restrictions on the upper boundary condition, and the lower boundary is an open boundary). In the data assimilation (or error correction) process, the stabilities of the two-sided boundaries are different. Correspondingly, it is also difficult to convert it into an unbounded variable. It is necessary to perform segmented (or interval) processing on the upper and lower boundaries, and ideally, the results of each segment (each interval) after conversion should be continuous and smooth. Mathematically, that is, ideally, the converted function is required to be continuous, and preferably, the first-order derivative function is continuous. In view of the above situation, taking the upper-bound bounded variable as an example, developing a method that can map the upper-bound bounded variable of water transportation into an unbounded variable is an effective idea to solve this problem. However, a scheme for inversely transforming the mapped unbounded variable back to the original variable must be supported. Thus, the reversible conversion between the upper-bound bounded variable and the unbounded variable of water transportation is realized. Summary of the Invention

[0005] In view of this, the present invention aims to propose a method and related products for realizing the reversible conversion between the upper-bound variable and the unbounded variable of water transportation to solve at least one of the problems existing in the above-mentioned prior art.

[0006] To achieve the above object, the technical solution of the present invention is realized as follows:

[0007] A method for realizing the reversible conversion between the upper-bound variable and the unbounded variable of water transportation includes the following steps:

[0008] S1. Select the upper-bound variable among the water transportation variable parameters and take values for the upper-bound variable;

[0009] S2. Convert the upper-bound variable into an unbounded variable;

[0010] S3. Prove that the mathematical transformation between the upper-bound variable and the unbounded variable is reversible;

[0011] S4. Prove that the first-order derivative is continuous at the positive transformation segmentation point;

[0012] S5. Prove that the first-order derivative is continuous at the inverse transformation segmentation point.

[0013] Further, in step S1, selecting the upper-bound variable among the water transportation variable parameters and taking values for the upper-bound variable includes:

[0014] Let any upper-bound variable be x, the upper boundary of its value range is x = UB, and the lower boundary is open, that is, the lower boundary of the value range is x = -∞, and the value range span is (-∞, UB).

[0015] Further, in step S2, converting the upper-bound variable into an unbounded variable includes:

[0016] Suppose there exists a point \(x = LiX\), \(y = LiX\). Taking this point as the boundary, when \(x\leq LiX\), \(x\) and \(y\) satisfy the linear function relationship \(y = x\).

[0017] When \(LiX\lt x\lt UB\), the bounded variable \(x\) with an upper boundary is transformed into an unbounded variable \(y\) through the following function:

[0018]

[0019] Therefore, the complete transformation function can be expressed in the form of a piecewise function as follows:

[0020]

[0021] At this time, the value range of the transformed \(y\) is \((-\infty, +\infty)\). Correspondingly, if it is necessary to reverse-transform the unbounded variable \(y\) back to the original bounded variable \(x\) with an upper boundary, the inverse function of \(f(x)\) is used, that is:

[0022]

[0023] Furthermore, in step S3, it is proved that the mathematical transformation between the upper-bounded variable and the unbounded variable is reversible, including:

[0024] Let \(x\) be an arbitrary upper-bounded variable, the upper boundary of its value range is \(x = UB\), and the lower boundary is open, that is, the lower boundary of the value range is \(x = -\infty\); the value range span is \((-\infty, UB)\);

[0025] First, perform a transformation to transform the variable \(x\) into an unbounded variable \(y\), that is:

[0026]

[0027] When the value range of \(x\) is \(LiX\lt x\lt UB\), the corresponding value range of the transformed \(y\) is \(y\gt LiX\); if a reverse transformation is performed again to transform the unbounded variable \(y\) into the variable \(x\_new\), then by looking up the transformation function in the corresponding interval, it can be known that:

[0028]

[0029] When the value range of \(x\) is \(x\leq LiX\), the corresponding value range of \(y\) is \(y\leq LiX\). Then, similarly, when performing a reverse transformation again to transform the unbounded variable \(y\) into the variable \(x\_new\), the corresponding mathematical process is:

[0030] \(x\_new = f\) -1 (y)=y = x;

[0031] Furthermore, in step S4, it is proved that the first derivative is continuous at the positive transformation segmentation point, including:

[0032] Divide the value range (-∞, UB) of the upper-bound bounded variable into two parts, namely: (-∞, LiX] and (LiX, UB); within the first interval, take the derivative of the transformation function f(x), that is, when x ≤ LiX:

[0033] y' = f'(x) = 1;

[0034] In the second interval, take the derivative of the transformation function f(x), that is, when LiX < x < UB:

[0035]

[0036] When x → LiX, the first-order derivative of the conversion function is:

[0037]

[0038] Therefore, the first-order derivative is continuous at the segmentation point x = LiX.

[0039] Furthermore, in step S5, proving the continuity of the first-order derivative at the inverse transformation segmentation point includes:

[0040] The inverse transformation has two intervals, y ≤ LiX and y > LiX; when y ≤ LiX, the derivative function of the inverse transformation function is:

[0041] x' = [f -1 (y)]' = 1;

[0042] When y > LiX, the first-order derivative of the inverse transformation function is:

[0043]

[0044] When y → LiX, the first-order derivative of the inverse transformation function is:

[0045]

[0046] Therefore, the first-order derivative is also continuous at the segmentation point y = LiX during the inverse transformation process.

[0047] An electronic device includes a processor and a memory communicatively connected to the processor and used to store instructions executable by the processor, and the processor is used to execute the method for realizing the reversible conversion between the water transportation upper-bound variable and the unbounded variable.

[0048] A server includes at least one processor and a memory communicatively connected to the processor, the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor to enable the at least one processor to execute the method for realizing the reversible conversion between the water transportation upper-bound variable and the unbounded variable.

[0049] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method for realizing the reversible conversion between the water transport upper boundary variable and the unbounded variable is implemented.

[0050] Compared with the prior art, the method and related products for realizing the reversible conversion between the water transport upper boundary variable and the unbounded variable according to the present invention have the following advantages:

[0051] (1) For the method and related products for realizing the reversible conversion between the water transport upper boundary variable and the unbounded variable according to the present invention, the method and device proposed by the present invention successfully realize the conversion of the bounded variable of the water transport upper boundary into an unbounded variable. This conversion can meet the requirements of some mathematical assimilation methods and mathematical models for unbounded variables during the water transport information processing and the water transport variable simulation and prediction processes. Compared with the traditional method of "adding intermediate steps in the algorithm and forcibly adjusting the corrected result within the boundary condition range", the present invention can ensure the continuity of the algorithm without destroying the basic assumptions of these peripheral nested algorithms and prevent the introduction of new errors. Theoretically, this makes the correction accuracy of the peripheral nested data assimilation and the model correction model higher, and the algorithm is more stable.

[0052] (2) For the method and related products for realizing the reversible conversion between the water transport upper boundary variable and the unbounded variable according to the present invention, the method proposed by the present invention divides the value range (-∞, UB) of the upper boundary bounded variable into two parts, namely: (-∞, LiX] and (LiX, UB). In the first interval, the linear function conversion relationship of y = x is directly adopted; in the second interval, a conversion relationship is constructed based on the logarithmic function. After conversion, the upper boundary extends infinitely to +∞, and the first derivative is continuous at the transition point between the two intervals. The overall idea is clear and concise, enabling the personnel using the present invention to intuitively grasp the corresponding relationship between the x and y variables before and after conversion. In addition, since the conversion relationship of y = x is used in the first interval, it is ensured that the nature of the variables before and after conversion is not changed in most cases, which is beneficial to reducing the complexity of subsequent further problem analysis.

[0053] (3) For the method and related products for realizing the reversible conversion between the water transport upper boundary variable and the unbounded variable according to the present invention, the method proposed by the present invention has reversibility. Moreover, this reversible conversion is based on a pure mathematical formula, rather than establishing a mapping table for one-to-one correspondence and intermediate interpolation. Such a characteristic enables the present invention to be used as a pre-stage or post-stage converter for any mathematical method, and this avoids the complex operations of establishing a mapping table and querying the mapping table. Since there is no intermediate interpolation, the introduction of interpolation errors is also avoided, reducing the memory occupation of the calculation module and accelerating the calculation speed. Description of the Drawings

[0054] The accompanying drawings, which form a part of the present invention, are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0055] Figure 1 It is a schematic diagram of the reversible transformation process between the upper-bounded variable x and the unbounded variable y described in the embodiment of the present invention;

[0056] Figure 2 It is a schematic diagram of the process flow of the method described in the embodiment of the present invention. Detailed implementation manners

[0057] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other.

[0058] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0059] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0060] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0061] As Figures 1 to 2 shown, a method for realizing the reversible conversion of the water transportation upper boundary variable and the unbounded variable includes the following steps:

[0062] S1. Select the upper-bounded variable among the water transportation variable parameters and take values for the upper-bounded variable;

[0063] S2. Convert the upper-bounded variable into an unbounded variable;

[0064] S3. Prove that the mathematical transformation between the upper-bounded variable and the unbounded variable is reversible;

[0065] S4. Prove that the first derivative is continuous at the segmentation point of the forward transformation;

[0066] S5. Prove that the first derivative is continuous at the segmentation point of the inverse transformation.

[0067] In a preferred embodiment of the present invention, the method includes:

[0068] Let any upper-bounded variable be x, the upper boundary of its value range is x = UB, and the lower boundary is open, that is, the lower boundary of the value range is x = -∞, and the value range span is (-∞, UB). Now it is necessary to convert this upper-boundary bounded variable x into an unbounded variable y, that is, it is required that the value range of y after conversion is (-∞, +∞).

[0069] The method provided by the present invention is: assume that there is a point x = LiX, y = LiX. Taking this point as the boundary, when x ≤ LiX, x and y satisfy the linear function relationship of y = x.

[0070] Before this, that is, when LiX < x < UB, the upper-boundary bounded variable x is converted into an unbounded variable y through the following function:

[0071]

[0072] Therefore, the complete transformation function can be expressed in the form of a piecewise function as follows:

[0073]

[0074] Correspondingly, if it is necessary to reverse-transform (or inverse-transform) the unbounded variable y back to the original upper-boundary bounded variable x, the inverse function of f(x) needs to be used, that is:

[0075]

[0076] Prove that this mathematical transformation is reversible:

[0077] Let x be an arbitrary upper-bounded variable, the upper boundary of its value range is x = UB, and the lower boundary is open, that is, the lower boundary of the value range is x = -∞. The value range span is (-∞, UB). Using the method provided by the present invention, first perform a transformation to transform the variable x into an unbounded variable y, that is, mathematically:

[0078]

[0079] It can be seen that when the value range of x is LiX < x < UB, the corresponding value range of the transformed y is y > LiX. If a reverse transformation is performed again to transform the unbounded variable y into the variable x_new, then by looking up the transformation function for the corresponding interval, it can be known that:

[0080]

[0081] When the value range of x is x ≤ LiX, the corresponding value range of y is y ≤ LiX. Then, similarly, when a reverse transformation is performed again to transform the unbounded variable y into the variable x_new, the corresponding mathematical process is:

[0082] x_new = f -1 (y) = y = x;

[0083] In summary, for any upper-bound bounded variable x, when the method of the present invention is applied, after one transformation and then one reverse transformation, the obtained x_new satisfies x_new = x. Therefore, the method for mutually converting the upper-bound variable and the unbounded variable proposed by the present invention is reversible mathematically.

[0084] Prove that the first derivative is continuous at the forward transformation segmentation point:

[0085] The method proposed by the present invention divides the value range (-∞, UB) of the upper-bound bounded variable into two parts, namely: (-∞, LiX] and (LiX, UB). In the first interval, the transformation function f(x) is differentiated, that is, when x ≤ LiX:

[0086] y' = f'(x) = 1;

[0087] In the second interval, the transformation function f(x) is differentiated, that is, when LiX < x < UB:

[0088]

[0089] When x → LiX, the first derivative of the conversion function is:

[0090]

[0091] Therefore, the proposed transformation method has a continuous first derivative at the segmentation point x = LiX.

[0092] Prove that the first derivative is continuous at the reverse transformation segmentation point:

[0093] Similarly, the reverse transformation also has two intervals, y ≤ LiX and y > LiX. When y ≤ LiX, the derivative function of the reverse transformation function is:

[0094] x' = [f -1 (y)]' = 1;

[0095] When y > LiX, the first derivative of the inverse transformation function is:

[0096]

[0097] When y → LiX, the first derivative of the inverse transformation function is:

[0098]

[0099] Therefore, the first derivative of the inverse transformation process is also continuous at the segmentation point y = LiX.

[0100] The present invention also provides an electronic device, including a processor and a memory communicatively connected to the processor and used for storing instructions executable by the processor, where the processor is used to execute the method for realizing the reversible conversion between the water transport upper boundary variable and the unbounded variable.

[0101] The present invention also provides a server, including at least one processor and a memory communicatively connected to the processor, where the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor to enable the at least one processor to execute the method for realizing the reversible conversion between the water transport upper boundary variable and the unbounded variable.

[0102] The present invention also provides a computer-readable storage medium storing a computer program, where the computer program, when executed by a processor, is the method for realizing the reversible conversion between the water transport upper boundary variable and the unbounded variable.

[0103] Advantages of the present invention:

[0104] (1) The method and device proposed by the present invention have successfully realized the conversion of the water transport upper boundary bounded variable to the unbounded variable. This conversion can meet the requirements of some mathematical assimilation methods and mathematical models for unbounded variables during the water transport information processing and water transport variable simulation and prediction processes. Compared with the traditional method of "adding intermediate steps in the algorithm and forcibly adjusting the corrected result within the boundary condition range", the present invention can not damage the basic assumptions of these peripheral nested algorithms, ensure the continuity of the algorithm, and prevent the introduction of new errors. From a theoretical perspective, this makes the correction accuracy of the peripheral nested data assimilation and model correction models higher, and the algorithm more stable.

[0105] (2) The method proposed by the present invention divides the value range (-∞, UB) of the upper-bound bounded variable into two parts, namely: (-∞, LiX] and (LiX, UB). In the first interval, the linear function conversion relationship of y = x is directly adopted; in the second interval, a conversion relationship is constructed based on the logarithmic function. After conversion, the upper boundary extends infinitely to +∞, and the first derivative is continuous at the transition point between the two intervals. The overall idea is clear and concise, enabling those who apply the present invention to intuitively grasp the corresponding relationship between the x and y variables before and after conversion. In addition, since the conversion relationship of y = x is used in the first interval, it ensures that the nature of the variables before and after conversion is not changed in most cases, which is beneficial to reducing the complexity of subsequent problem analysis.

[0106] (3) The method proposed by the present invention is reversible. Moreover, this reversible conversion is based on pure mathematical formulas, rather than establishing a mapping table for one-to-one correspondence and intermediate interpolation. Such a characteristic enables the present invention to be used as a pre-stage or post-stage converter for any mathematical method. And in this way, the complex operations of establishing a mapping table and querying the mapping table are avoided. Because there is no intermediate interpolation, the interpolation error is also avoided, reducing the memory occupation of the calculation module and accelerating the calculation speed.

[0107] Example 1

[0108] Suppose a water transportation variable x represents the potential energy difference of the water flow relative to the source (less than or equal to 0), that is, the value range of the variable x is (-∞, 0) meters. Then, the water transportation variable x can be regarded as a typical upper-bound bounded variable. In order to meet the requirements of some mathematical assimilation methods and mathematical models for unbounded variables, it needs to be converted into an unbounded variable y. And it is required that this conversion is reversible mathematically.

[0109] Applying the method of the present invention, the steps are as follows:

[0110] ① Identify the upper boundary point of x and set the conversion parameter LiX. The conversion parameter can be set as needed, only need to meet UB > LiX. In this embodiment,

[0111] UB = 0;

[0112] LiX = -10;

[0113] ② Use the calculation module to apply the formula proposed by the present invention to construct the corresponding conversion function, convert the upper-bound bounded variable x into an unbounded variable y, and output and store the result in the result storage module as follows:

[0114]

[0115] ③ If it is necessary to inversely transform the unbounded variable y back to the upper-bounded variable x, the calculation module is used to construct the corresponding inverse transformation function by applying the formula proposed in the present invention, and the result is output and stored in the result storage module as follows:

[0116]

[0117] In this embodiment, the schematic diagram of the reversible transformation process between the upper-bounded variable x and the unbounded variable y is as Figure 1 shown. Figure 1 In, (a) represents the process of converting the upper-bounded variable x into the unbounded variable y, (b) represents the relationship between the original upper-bounded variable x and x_new obtained after two conversions, and (c) represents the process of inversely converting the unbounded variable y back to the upper-bounded variable (using x_new to represent the inverse conversion result, distinguished from the initial variable x).

[0118] From Figure 1 it can be seen that the method proposed in the present invention divides the value range (-∞, 0) of the upper-bounded variable into two parts, namely: (-∞, -10] and (-10, 0). In the first interval ( Figure 1 . the range marked in cyan), the linear function conversion relationship of y = x is directly adopted; in the second interval, the conversion relationship is constructed based on the logarithmic function, and after conversion, the upper boundary extends infinitely to +∞; and the first derivative is continuous at the transition point between the two intervals.

[0119] In this embodiment, the conversion processes within two intervals are exemplified. In the first interval, x1 = -5, and the corresponding y1 = -3.0685 after conversion. After another inverse conversion calculation, the obtained x_new1 = -5; in the second interval, x2 = -20, and the corresponding y2 = -20 after conversion. After another inverse conversion calculation, the obtained x_new2 = -20; x3 = -30, and the corresponding y3 = -30 after conversion. After another inverse conversion calculation, the obtained x_new3 = -30. Intuitively, it shows that the conversion method proposed in the present invention is reversible.

[0120] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for realizing reversible conversion between upper bound variables and unbounded variables in water transport, characterized in that: It includes the following steps: S1. Select the upper-bounded variables among the water transport variable parameters and assign values to the upper-bounded variables. S2. Transform the upper-bounded variables into unbounded variables. S3. Prove that the mathematical transformation between the upper-bounded variables and the unbounded variables is reversible. S4. Prove that the first-order derivative is continuous at the positive transformation segmentation point. S5. Prove that the first-order derivative is continuous at the inverse transformation segmentation point.

2. A method for realizing reversible conversion between upper bound variables and unbounded variables in water transport according to claim 1, characterized in that: In step S1, when selecting the upper-bounded variables among the water transport variable parameters and assigning values to the upper-bounded variables, it includes: Let any upper-bounded variable be x, the upper boundary of its value range is x = UB, and the lower boundary is open, that is, the lower boundary of the value range is x = -∞, and the value range span is (-∞, UB).

3. A method for realizing reversible conversion between upper bound variables and unbounded variables in water transport according to claim 1, characterized in that: In step S2, when transforming the upper-bounded variables into unbounded variables, it includes: Suppose there exists a point x = LiX, y = LiX. Taking this point as the boundary, when x ≤ LiX, x and y satisfy the linear function relationship y = x. When LiX < x < UB, the variable x with a bounded upper boundary is transformed into an unbounded variable y through the following function: Therefore, the complete transformation function can be expressed in the form of a piecewise function as follows: At this time, the value range of the transformed y is (-∞, +∞). Correspondingly, if it is necessary to reverse-transform the unbounded variable y back to the original upper-bound bounded variable x, use the inverse function of f(x), that is:

4. A method for realizing reversible conversion between upper bound variables and unbounded variables in water transport according to claim 1, characterized in that: In step S3, when proving that the mathematical transformation between the upper-bounded variables and the unbounded variables is reversible, it includes: Let x be an arbitrary upper-bound bounded variable, the upper boundary of its value range is x = UB, and the lower boundary is open, that is, the lower boundary of the value range is x = -∞; the value range span is (-∞, UB); First, perform a transformation to transform the variable x into an unbounded variable y, that is: When the value range of x is LiX < x < UB, the corresponding value range of the transformed y is y > LiX; if a reverse transformation is performed again to transform the unbounded variable y into the variable x_new, then by looking up the transformation function in the corresponding interval, it can be known that: When the value range of x is x ≤ LiX, the corresponding value range of y is y ≤ LiX; then, similarly, when performing a reverse transformation again to transform the unbounded variable y into the variable x_new, the corresponding mathematical process is: x_new=f -1 (y)=y=x。 5. A method for realizing reversible conversion between upper bound variables and unbounded variables in water transport according to claim 1, characterized in that: In step S4, when proving that the first-order derivative is continuous at the positive transformation segmentation point, it includes: Divide the value range (-∞, UB) of the upper-bound bounded variable into two parts, that is: (-∞, LiX] and (LiX, UB); in the first interval, take the derivative of the transformation function f(x), that is, when x ≤ LiX: y' = f'(x) = 1; In the second interval, take the derivative of the transformation function f(x), that is, when LiX < x < UB: When x → LiX, the first-order derivative of the conversion function is: Therefore, the first-order derivative is continuous at the segmentation point x = LiX.

6. A method for realizing reversible conversion between upper bound variables and unbounded variables in water transport according to claim 1, characterized in that: In step S5, when proving that the first-order derivative is continuous at the inverse transformation segmentation point, it includes: For the inverse transformation, there are two intervals, y ≤ LiX and y > LiX; when y ≤ LiX, the derivative function of the inverse transformation function is: x'=[f -1 (y)]'=1; When y > LiX, the first-order derivative of the inverse transformation function is: When y → LiX, the first-order derivative of the inverse transformation function is: Therefore, the first-order derivative is also continuous at the segmentation point y = LiX during the inverse transformation process.

7. An electronic device, comprising a processor and a memory connected to the processor for storing instructions executable by the processor, characterized in that: The processor is used to execute the method for realizing reversible conversion between upper boundary variables and unbounded variables in water transport as described in any one of claims 1-6 above.

8. A server, characterized in that: It includes at least one processor and a memory communicatively connected to the processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the processor so that the at least one processor executes the method for realizing reversible conversion between upper boundary variables and unbounded variables in water transport as described in any one of claims 1-6.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method for realizing reversible conversion between upper boundary variables and unbounded variables in water transport as described in any one of claims 1 to 6 is implemented.

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