Digital twin multi-dimensional data visualization method and system based on OGC standard

Abstract

The application relates to the technical field of multi-dimensional data visualization, in particular to a digital twin multi-dimensional data visualization method and system based on an OGC standard, and a visualization special effect signal analysis module in the system is used for calculating a dynamic interpolation position corresponding to a current time key frame state attribute in a WebGPU rendering pipeline, performing business rule judgment based on GPU executable instructions of the current time key frame, and outputting a visualization special effect signal when the business rule is triggered. The application can break through the limitation of a standard 3D Tiles static data model in a manner of newly adding a time sequence slot, and construct a time-space integrated storage structure facing dynamic objects; the application can realize dynamic interpolation of positions and attributes in key frame state data, and can effectively reduce rendering delay; the application can insert or cover original time sequence slots with a rule judgment structure as a new key frame through a differential update package, so that self-correction of time sequence slot key frame data is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of multi-dimensional data visualization, in particular to a digital twin multi-dimensional data visualization method and system based on OGC standards. BACKGROUND

[0002] As a virtual mapping of the physical world, digital twin needs to integrate multi-source heterogeneous data (such as geospatial, IoT sensors, BIM models, real-time business data), and support dynamic interaction and high-fidelity visualization. Although OGC standards (such as WMS, WMTS, WFS, 3D Tiles) provide specifications for geographic data interoperability, there are still defects in the digital twin scenario, mainly reflected in that the traditional OGC 3D Tiles only supports static models, focuses on the publication of static data, but lacks efficient encoding and transmission mechanisms for real-time streaming data (such as sensor time series data), and full tile updates are often needed for dynamic objects, thereby causing bandwidth waste; at the same time, W3C semantic rules are usually executed on the CPU side, which is greatly disconnected from the GPU rendering pipeline, resulting in a large rule triggering delay; and the existing WebGL shader lacks a time series key frame interpolation mechanism, and dynamic properties need to be returned frame by frame, which aggravates the data transmission load; therefore, the existing technology has great defects. SUMMARY

[0003] The purpose of the present application is to provide a digital twin multi-dimensional data visualization method and system based on OGC standards to solve the problems raised in the background.

[0004] In order to solve the above technical problems, the present application provides the following technical scheme: a digital twin multi-dimensional data visualization method based on OGC standards, the method comprising:

[0005] S1, extending a time series slot in the batch attribute table of OGC 3D Tiles, storing the key frame state of the object in the preset length of the time window, and constructing a dynamic attribute stream in the time series enhanced 3D Tiles data layer;

[0006] S2, based on the dynamic attribute stream in the time series enhanced 3D Tiles data layer, performing linear interpolation on the key frame state of the current time in the GPU shader, and extracting the state attribute of the current time key frame;

[0007] S3, obtaining RDF / SPARQL business rules, converting RDF triples or SPARQL query conditions into a logical expression tree, and combining the state attribute extraction result of the current time key frame to obtain GPU executable instructions based on the current time key frame;

[0008] S4, in the WebGPU rendering pipeline, a dynamic interpolation position corresponding to a current time key frame state attribute is calculated, a business rule judgment is performed based on GPU executable instructions of the current time key frame, and a visual special effect signal is output when the business rule is triggered.

[0009] S5, a differential update package is generated according to the rule trigger signal, and the differential update package is returned to the time sequence data layer to update the time sequence slot key frame.

[0010] Further, the key frame state of the storage object in the preset length of the time window in S1 includes a time stamp sequence, a position key frame sequence and an attribute key frame sequence corresponding to the extended time sequence slot key frame.

[0011] The number of elements in the time stamp sequence, the position key frame sequence and the attribute key frame sequence is the same, and each element corresponds to a key frame; the element in the attribute key frame sequence is a business attribute vector of the corresponding key frame, and the business attribute vector is a matrix composed of attribute values of multiple different business attribute types, and the number of business attribute types is preset.

[0012] The attribute key frame sequence in the key frame state of the storage object in the preset length of the time window is taken as a dynamic attribute stream in the time sequence enhanced 3D Tiles data layer.

[0013] The application can break through the limitation of the standard 3D Tiles static data model by extending the Batch Table structure of OGC 3D Tiles, adding a time sequence slot and storing the key frame state of the object in the time window, and can construct a space-time integrated storage structure for dynamic objects.

[0014] Further, the state attribute of the current time key frame involved in S2 is calculated according to the following formula: ,

[0015] Wherein, BD represents the state attribute of the current time key frame; ξ represents the time progress coefficient corresponding to the current time; TD represents the current time; T i represents the time stamp in the time stamp sequence that is earlier than the current time and has the minimum interval time length with the current time; T i+1 represents the time stamp in the time stamp sequence that is later than the current time and has the minimum interval time length with the current time; B i represents the business attribute vector in the attribute key frame sequence whose corresponding time stamp is T i ; B i+1 represents the business attribute vector in the attribute key frame sequence whose corresponding time stamp is T i+1 .

[0016] In the present application, the time progress coefficient is calculated in real time in the shader, and the dynamic interpolation operation of position and attribute is realized according to the time progress coefficient obtained by real-time calculation, compared with the traditional CPU interpolation scheme, which can effectively reduce the rendering delay, and the essence of the present application is to unload the time sequence calculation to the GPU, thereby realizing the hardware-level interpolation acceleration.

[0017] Further, the S3 comprises:

[0018] S31, the input RDF triple or SPARQL query condition is parsed into a logical expression tree;

[0019] S32, the logical expression tree is partially evaluated in combination with the state attribute of the current time key frame;

[0020] S33, the logical expression tree after partial evaluation is compiled into a WGSL code segment executable by the GPU shader;

[0021] In the process of the S32, when the tree node is an attribute type, the attribute of the corresponding tree node is replaced by a preset constant value corresponding to the corresponding attribute type; when all child nodes of the tree node are constant values, the value of the node is calculated and replaced by a constant node; the logical expression tree after partial evaluation is an expression tree whose attribute type of the tree node contains each attribute type involved by the state attribute of the previous time key frame and is minimized; if the entire expression tree is constant after partial evaluation, a WGSL code segment returning the constant value is generated; each tree node of the logical expression tree includes 0 or more child nodes of the corresponding tree node, and each child node is a tree node.

[0022] The present application parses the W3C RDF / SPARQL rule into a logical expression tree, and dynamically generates a WGSL code segment (GPU executable instruction based on the current time key frame) executable by the GPU shader of the state attribute of the current time key frame through the internal node condition of the logical expression tree; the present application can open the heterogeneous computing cooperative channel of the semantic rule and the rendering pipeline.

[0023] Further, the S4 calculates the calculation formula related to the dynamic interpolation position corresponding to the state attribute of the current time key frame as follows: ,

[0024] Wherein, PD represents the dynamic interpolation position corresponding to BD; P i represents the state position of the key frame corresponding to the timestamp T i in the position key frame sequence; P i+1 represents the state position of the key frame corresponding to the timestamp T i+1 in the position key frame sequence;

[0025] The visual effect signal outputted by the rule trigger includes a target object of the effect trigger, a business attribute vector, and a timestamp.

[0026] Further, the differential update package in S5 includes the visual effect signal outputted by the rule trigger, an interval time length between the timestamp in the visual effect signal and any one element corresponding timestamp in the corresponding timestamp sequence in the extended time sequence slot, and a vector difference between the business attribute vector in the visual effect signal and any one element corresponding business attribute vector in the corresponding attribute key frame sequence in the extended time sequence slot;

[0027] Based on the obtained insertion update package, an update demand evaluation coefficient of the current time key frame is calculated, and a calculation formula involved is as follows: ,

[0028] wherein, PX1 represents the update demand evaluation coefficient of the current time key frame; BC i represents a module length corresponding to a vector difference between BD and B i ; BC i+1 represents a module length corresponding to a vector difference between BD and B i+1 ;

[0029] PX1 is compared with a first preset evaluation coefficient Y1,

[0030] when PX1 < Y1, a business attribute mutation coefficient BS i between a previous key frame corresponding to the key frame of B i+1 and the key frame of B （i-1，i+1） is calculated, and BS （i-1，i+1） is further compared with a preset mutation coefficient,

[0031] if BS （i-1，i+1） is greater than or equal to the preset mutation coefficient, the current time key frame is inserted between the key frames corresponding to B i and B i+1 respectively, to obtain an updated time sequence slot key frame; if BS （i-1，i+1） is less than the preset mutation coefficient, the current time key frame is used to replace the key frame corresponding to B i , to obtain an updated time sequence slot key frame;

[0032] when Y1 ≤ PX1, the current time key frame is inserted between the key frames corresponding to B i and B i+1 respectively, to obtain an updated time sequence slot key frame;

[0033] A calculation formula involved in the calculation of the business attribute mutation coefficient between any two key frames is as follows: ,

[0034] Wherein, BS represents the attribute mutation coefficient between the corresponding two key frames; SPQ represents the average value of the absolute value of the difference between the attribute value of each service attribute type corresponding to the service attribute vector of the previous key frame in the corresponding two key frames and the attribute value of the same service attribute type in the current key frame, divided by the difference between the time stamp of the previous key frame and the current time; SPH represents the average value of the absolute value of the difference between the attribute value of each service attribute type corresponding to the service attribute vector of the latter key frame in the corresponding two key frames and the attribute value of the same service attribute type in the current key frame, divided by the difference between the time stamp of the latter key frame and the current time; min{} represents the minimum value function; max{} represents the maximum value function.

[0035] The application can insert or cover the original time slot with the rule judgment structure as a new key frame through the differential update package, and realize self-correction of the key frame data of the time slot.

[0036] The digital twin multi-dimensional data visualization system based on the OGC standard comprises:

[0037] A dynamic attribute flow construction module is used for expanding the time slot in the batch attribute table of OGC 3D Tiles, storing the key frame state of an object in a preset length of time window, and constructing a dynamic attribute flow in a time-enhanced 3D Tiles data layer.

[0038] A state attribute extraction module is used for performing linear interpolation on the key frame state at the current time in a GPU shader based on the dynamic attribute flow in the time-enhanced 3D Tiles data layer, and extracting the state attribute of the key frame at the current time.

[0039] A GPU execution acquisition module is used for acquiring an RDF / SPARQL service rule, converting an RDF triple or a SPARQL query condition into a logical expression tree, and combining the state attribute extraction result of the key frame at the current time to obtain a GPU executable instruction based on the key frame at the current time.

[0040] A visual special effect signal analysis module is used for calculating a dynamic interpolation position corresponding to the state attribute of the key frame at the current time in a WebGPU rendering pipeline, performing service rule judgment based on the GPU executable instruction of the key frame at the current time, and outputting a visual special effect signal when the service rule is triggered.

[0041] A time slot key frame update module is used for generating a differential update package according to a rule trigger signal, and returning the differential update package to the time sequence data layer to update the time slot key frame.

[0042] Further, the GPU execution acquisition module comprises a logical expression tree acquisition unit and an execution instruction analysis unit.

[0043] The logic expression tree acquisition unit is used for acquiring RDF / SPARQL business rules, and converting RDF triples or SPARQL query conditions into a logic expression tree.

[0044] The execution instruction analysis unit extracts the result of the state attribute of the current time key frame to obtain GPU executable instructions based on the current time key frame.

[0045] Further, the visual special effect signal analysis module comprises an interpolation position acquisition unit and a special effect signal output unit,

[0046] The interpolation position acquisition unit is used for calculating a dynamic interpolation position corresponding to the state attribute of the current time key frame in a WebGPU rendering pipeline.

[0047] The special effect signal output unit performs business rule judgment based on the GPU executable instructions of the current time key frame, and outputs a visual special effect signal when the business rule is triggered.

[0048] Compared with the prior art, the present application has the following beneficial effects:

[0049] The present application can break through the limitation of the standard 3D Tiles static data model by adding a time sequence slot, and construct a space-time integrated storage structure for dynamic objects.

[0050] The present application introduces the concept of time progress coefficient to realize dynamic interpolation of position and attribute in key frame state data, which can effectively reduce rendering delay compared with traditional CPU interpolation scheme.

[0051] The present application can parse RDF / SPARQL rules into a logic expression tree, and then dynamically generate GPU executable instructions of the current time key frame, effectively opening the heterogeneous computing and collaborative channel of semantic rules and rendering pipeline.

[0052] The present application can insert or cover the original time sequence slot with the rule judgment structure as a new key frame through the differential update package, realize self-correction of the time sequence slot key frame data, avoid full update of the tile, and save bandwidth resources. BRIEF DESCRIPTION OF DRAWINGS

[0053] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, which together with the embodiments of the present application, serve to explain the present application, and do not constitute a limitation of the present application. In the drawings:

[0054] Fig. 1 is a structural schematic diagram of the digital twin multi-dimensional data visualization system of the present application based on the OGC standard;

[0055] Fig. 2 is a flowchart of the method for digital twin multi-dimensional data visualization based on the OGC standard of the present application. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0057] Please refer to Figs. 1-2 , the present application provides technical solutions: as Fig. 1 shown, the present embodiment provides a digital twin multi-dimensional data visualization system based on the OGC standard, which comprises:

[0058] A dynamic attribute flow construction module is used to expand the time slot in the batch attribute table of OGC 3D Tiles, store the key frame state of the object in the preset length of the time window, and construct the dynamic attribute flow in the time-enhanced 3D Tiles data layer.

[0059] A state attribute extraction module is used to perform linear interpolation on the key frame state of the current time in the GPU shader based on the dynamic attribute flow in the time-enhanced 3D Tiles data layer, and extract the state attribute of the key frame of the current time.

[0060] A GPU execution acquisition module comprises a logical expression tree acquisition unit and an execution instruction analysis unit,

[0061] The logical expression tree acquisition unit is used to acquire RDF / SPARQL business rules, and convert RDF triples or SPARQL query conditions into a logical expression tree.

[0062] The execution instruction analysis unit obtains GPU executable instructions based on the key frame of the current time in combination with the state attribute extraction result of the key frame of the current time.

[0063] A visual special effect signal analysis module comprises an interpolation position acquisition unit and a special effect signal output unit,

[0064] The interpolation position acquisition unit is used to calculate the dynamic interpolation position corresponding to the state attribute of the key frame of the current time in the WebGPU rendering pipeline.

[0065] The special effect signal output unit performs business rule judgment based on the GPU executable instructions of the key frame of the current time, and outputs a visual special effect signal when the business rule is triggered.

[0066] a time slot key frame updating module configured to generate a differential update package according to a rule trigger signal and return the differential update package to the time slot data layer to update the time slot key frame.

[0067] As shown in Fig. 2 , the embodiment provides an OGC standard-based digital twin multi-dimensional data visualization method, which comprises the following steps:

[0068] S1. Extending a time slot in a batch attribute table of OGC 3D Tiles to store key frame states of an object in a preset length of time window, and constructing a dynamic attribute stream in a time slot enhanced 3D Tiles data layer.

[0069] The step of storing the key frame states of the object in the preset length of time window in S1 comprises a timestamp sequence corresponding to the key frames in the extended time slot, a position key frame sequence and an attribute key frame sequence.

[0070] The number of elements in the timestamp sequence, the position key frame sequence and the attribute key frame sequence is the same, and each element corresponds to a key frame; the elements in the attribute key frame sequence are business attribute vectors of the corresponding key frames, the business attribute vector is a matrix composed of attribute values of different business attribute types, and the number of business attribute types is preset.

[0071] In the embodiment, if the preset business attribute type is four, and the attribute values corresponding to the four business attribute types are sequentially denoted as w1, w2, w3 and w4, then the corresponding business attribute vector is .

[0072] The attribute key frame sequence in the key frame states of the object in the preset length of time window is taken as the dynamic attribute stream in the time slot enhanced 3D Tiles data layer.

[0073] S2. Linearly interpolating the key frame state at the current time in a GPU shader based on the dynamic attribute stream in the time slot enhanced 3D Tiles data layer, and extracting the state attribute of the key frame at the current time.

[0074] The calculation formula involved in the step of extracting the state attribute of the key frame at the current time in S2 is as follows: ,

[0075] wherein, BD represents the state attribute of the key frame at the current time; ξ represents a time progress coefficient corresponding to the current time; TD represents the current time; T i represents a timestamp in the timestamp sequence that is earlier than the current time and has the minimum interval length with the current time; T i+1represents a timestamp in the timestamp sequence that is later than the current time and has the minimum interval with the current time;B i represents a service attribute vector in the attribute key frame sequence with a corresponding timestamp T i i+1 represents a service attribute vector in the attribute key frame sequence with a corresponding timestamp T i+1

[0076] S3, obtaining an RDF / SPARQL service rule, converting an RDF triple or a SPARQL query condition into a logical expression tree, and combining a state attribute of a current time key frame to extract a result, to obtain a GPU executable instruction based on the current time key frame;

[0077] The S3 comprises:

[0078] S31, parsing an inputted RDF triple or SPARQL query condition into a logical expression tree;

[0079] S32, combining a state attribute of a current time key frame to perform partial evaluation on the logical expression tree;

[0080] S33, compiling the logical expression tree after the partial evaluation into a WGSL code segment executable by a GPU shader;

[0081] In the process of performing the partial evaluation on the logical expression tree by the S32, when a tree node is of an attribute type, an attribute of the corresponding tree node is replaced by a preset constant value corresponding to the attribute type; when all child nodes of the tree node are constant values, a value of the node is calculated and replaced by a constant node; the logical expression tree after the partial evaluation is an expression tree that is of the attribute type of the tree node and simultaneously contains each attribute type involved by the state attribute of the previous time key frame and is minimized; if the entire expression tree is constant after the partial evaluation, a WGSL code segment returning the constant value is generated; each tree node of the logical expression tree comprises 0 or more child nodes of the corresponding tree node, and each child node is a tree node.

[0082] In the embodiment, the types of the tree nodes of the logical expression tree comprise leaf nodes and non-leaf nodes, the leaf nodes correspond to operation trees, and the operation trees correspond to attribute types or attribute values corresponding to the attribute types; the non-leaf nodes correspond to operators, and the operators correspond to greater than, less than, equal to, and operations, or operations, not operations, etc.

[0083] S4, in a WebGPU rendering pipeline, calculating a dynamic interpolation position corresponding to a state attribute of a current time key frame, performing service rule judgment based on the GPU executable instruction of the current time key frame, and outputting a visual special effect signal when the service rule is triggered;

[0084] ​​The calculation formula related to the calculation of the dynamic interpolation position corresponding to the current time key frame state attribute in S4 is as follows: ,

[0085] Wherein, PD represents the dynamic interpolation position corresponding to the BD; P i represents the key frame state position corresponding to the timestamp T i in the position key frame sequence; P i+1 represents the key frame state position corresponding to the timestamp T i+1 in the position key frame sequence;

[0086] The visual effect signal output when the rule is triggered includes the target object of the effect trigger, the business attribute vector and the timestamp.

[0087] The data flow synchronization mechanism of this part in the embodiment is as follows: the CPU writes the timing data and the rule parameters to the GPU, the GPU calculates the dynamic interpolation position corresponding to the interpolation attribute in the vertex shader for the rendering frame, and transmits it to the fragment shader, the fragment shader obtains the dynamic attribute in the current fragment, and calls the GPU executable instruction based on the current time key frame to perform the business rule judgment, and according to the true or false of the judgment result, it is determined whether the effect is triggered.

[0088] S5, according to the rule trigger signal, generate a differential update package, and return the differential update package to the timing data layer, update the timing slot key frame.

[0089] The differential update package in S5 includes the visual effect signal output when the rule is triggered, the interval time length between the timestamp in the visual effect signal and the corresponding timestamp in any element in the extended timing slot, and the vector difference between the business attribute vector in the visual effect signal and the corresponding business attribute vector in any element in the extended timing slot.

[0090] Based on the obtained insertion update package, the update demand evaluation coefficient of the current time key frame is calculated, and the calculation formula is as follows: ,

[0091] Wherein, PX1 represents the update demand evaluation coefficient of the current time key frame; BC i represents the module length corresponding to the vector difference between the BD and the B i ; BC i+1 represents the module length corresponding to the vector difference between the BD and the B i+1 .

[0092] PX1 and the first preset evaluation coefficient Y1 are compared,

[0093] When PX1 < Y1, the previous key frame corresponding to the key frame of B i is calculated, and the Bi+1 Attribute mutation coefficient BS between corresponding key frames （i-1，i+1） , further BS （i-1，i+1） Compared with the preset mutation coefficient,

[0094] If BS （i-1，i+1） If it is greater than or equal to the preset mutation coefficient, the current time key frame is inserted into B i With B i+1 Between the corresponding key frames, the updated time slot key frame is obtained; if BS （i-1，i+1） If it is less than the preset mutation coefficient, the current time key frame will be overwritten by B i The corresponding key frame obtains the updated timing slot key frame;

[0095] When Y1≤PX1, insert the current time key frame into B i With B i+1 Between the corresponding key frames, the updated time slot key frames are obtained;

[0096] The calculation formula for calculating the attribute mutation coefficient between any two key frames is as follows: ,

[0097] Among them, BS represents the attribute mutation coefficient between the corresponding two key frames; SPQ represents the quotient of the average value of the absolute value of the difference between the attribute value of each business attribute type corresponding to the business attribute vector of the previous key frame in the corresponding two key frames and the attribute value of the same business attribute type in the business attribute vector of the current key frame, divided by the difference between the timestamp of the previous key frame and the current time; SPH represents the quotient of the average value of the absolute value of the difference between the attribute value of each business attribute type corresponding to the business attribute vector of the latter key frame in the corresponding two key frames and the attribute value of the same business attribute type in the business attribute vector of the current key frame, divided by the difference between the timestamp of the latter key frame and the current time; min{} represents the minimum value function; max{} represents the maximum value function.

[0098] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0099] Finally, it should be noted that the above only describes the preferred embodiments of the present application and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art will appreciate that the technical solutions described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalent ones. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A digital twin multidimensional data visualization method based on the OGC standard, characterized by: The method comprises: S1. Extend the time slots in the batch attribute table of OGC 3D Tiles to store the key frame states of objects within a time window of preset length, and build a dynamic attribute stream in the time-enhanced 3D Tiles data layer; S2. Based on the dynamic attribute flow in the timing-enhanced 3D Tiles data layer, linear interpolation is performed on the key frame state at the current time in the GPU shader to extract the state attributes of the key frame at the current time; S3. Obtain RDF / SPARQL business rules, convert RDF triples or SPARQL query conditions into a logical expression tree, and extract the results based on the state attributes of the current time key frame to obtain GPU executable instructions based on the current time key frame; S4. In the WebGPU rendering pipeline, the dynamic interpolation position corresponding to the state attribute of the current time keyframe is calculated, the business rule determination is performed based on the GPU executable instructions of the current time keyframe, and a visual special effect signal is output when the business rule is triggered; S5. Generate a differential update package based on the rule trigger signal, and transmit the differential update package back to the time series data layer to update the time series slot key frame; The differential update package in S5 includes the visual special effect signal output when the rule is triggered, the interval between the timestamp in the visual special effect signal and the timestamp corresponding to any element in the corresponding timestamp sequence in the extended timing slot, and the vector difference between the business attribute vector in the visual special effect signal and the business attribute vector corresponding to any element in the corresponding attribute key frame sequence in the extended timing slot; Based on the obtained inserted update package, the update demand evaluation coefficient of the current time key frame is calculated. The calculation formula involved is as follows: , Among them, PX1 represents the update demand evaluation coefficient of the current time key frame; BC i Indicates BD and B i The modulus length corresponding to the vector difference between them; BC i+1 Indicates BD and B i+1 The modulus length corresponding to the vector difference between them; T i Indicates the timestamp in the timestamp sequence that is earlier than the current time and has the smallest time interval with the current time; T i+1 Indicates the timestamp in the timestamp sequence that is later than the current time and has the smallest time interval with the current time; B i Indicates that the corresponding timestamp in the attribute keyframe sequence is T i Business attribute vector of B i+1 Indicates that the corresponding timestamp in the attribute keyframe sequence is T i+1 The business attribute vector of BD represents the state attribute of the current time key frame; Compare PX1 with the first preset evaluation coefficient Y1, When PX1<Y1, calculate B i The previous key frame of the corresponding key frame and B i+1 Attribute mutation coefficient BS between corresponding key frames （i-1，i+1） , further BS （i-1，i+1） Compared with the preset mutation coefficient, If BS （i-1，i+1） If it is greater than or equal to the preset mutation coefficient, the current time key frame is inserted into B i With B i+1 Between the corresponding key frames, the updated time slot key frame is obtained; if BS （i-1，i+1） If it is less than the preset mutation coefficient, the current time key frame will be overwritten by B i The corresponding key frame obtains the updated timing slot key frame; When Y1≤PX1, insert the current time key frame into B i With B i+1 Between the corresponding key frames, the updated time slot key frames are obtained; The calculation formula for calculating the attribute mutation coefficient between any two key frames is as follows: , Among them, BS represents the attribute mutation coefficient between the corresponding two key frames; SPQ represents the quotient of the average value of the absolute value of the difference between the attribute value of each business attribute type corresponding to the business attribute vector of the previous key frame in the corresponding two key frames and the attribute value of the same business attribute type in the business attribute vector of the current key frame, divided by the difference between the timestamp of the previous key frame and the current time; SPH represents the quotient of the average value of the absolute value of the difference between the attribute value of each business attribute type corresponding to the business attribute vector of the latter key frame in the corresponding two key frames and the attribute value of the same business attribute type in the business attribute vector of the current key frame, divided by the difference between the timestamp of the latter key frame and the current time; min{} represents the minimum value function; max{} represents the maximum value function.

2. The digital twin multidimensional data visualization method based on the OGC standard according to claim 1 is characterized in that: The key frame state of the object stored in S1 within a time window of a preset length includes a timestamp sequence, a position key frame sequence, and an attribute key frame sequence corresponding to the key frame in the extended time slot; The number of elements in the timestamp sequence, the position key frame sequence, and the attribute key frame sequence is the same, and each element corresponds to a key frame; the elements in the attribute key frame sequence are the service attribute vectors of the corresponding key frame, and the service attribute vector is a matrix composed of attribute values ​​of multiple different service attribute types, and the number of service attribute types is preset; The attribute keyframe sequence in the keyframe state of the stored object within a preset time window is used as a dynamic attribute stream in a timing-enhanced 3D Tiles data layer.

3. The digital twin multidimensional data visualization method based on the OGC standard according to claim 1 is characterized in that: The calculation formula involved in extracting the state attributes of the current time key frame in S2 is as follows: , Among them, BD represents the state attribute of the key frame at the current time; ξ represents the time progress coefficient corresponding to the current time; TD represents the current time; T i Indicates the timestamp in the timestamp sequence that is earlier than the current time and has the smallest time interval with the current time; T i+1 Indicates the timestamp in the timestamp sequence that is later than the current time and has the smallest time interval with the current time; B i Indicates that the corresponding timestamp in the attribute keyframe sequence is T i Business attribute vector of B i+1 Indicates that the corresponding timestamp in the attribute keyframe sequence is T i+1 Business attribute vector.

4. The digital twin multidimensional data visualization method based on the OGC standard according to claim 1 is characterized in that: Said S3 includes: S31, parsing the input RDF triple or SPARQL query condition into a logical expression tree; S32. Partially evaluate the logical expression tree based on the state attributes of the current time key frame; S33, compile the partially evaluated logical expression tree into a WGSL code snippet executable by the GPU shader; In the process of partial evaluation of the logical expression tree by S32, when the tree node is an attribute type, the attribute of the corresponding tree node is replaced with a preset constant value corresponding to the corresponding attribute type; when all child nodes of the tree node are constant values, the value of the node is calculated and replaced with a constant node; the logical expression tree after partial evaluation is an expression tree that is minimized and includes the attribute type of the tree node and the various attribute types involved in the state attributes of the previous time key frame; if the entire expression tree is a constant after partial evaluation, a WGSL code fragment that returns the constant value is generated; each tree node of the logical expression tree includes 0 or more child nodes of the corresponding tree node, and each child node is a tree node.

5. The digital twin multidimensional data visualization method based on the OGC standard according to claim 3 is characterized in that: The calculation formula involved in calculating the dynamic interpolation position corresponding to the current time key frame state attribute in S4 is as follows: , Among them, PD represents the dynamic interpolation position corresponding to BD; P i Indicates that the corresponding timestamp in the position keyframe sequence is T i The key frame state position of P i+1 Indicates that the corresponding timestamp in the position keyframe sequence is T i+1 The key frame state position; The visual special effect signal output when the rule is triggered includes the target object of the special effect trigger, the business attribute vector and the timestamp.

6. A digital twin multidimensional data visualization system based on the OGC standard, applying the digital twin multidimensional data visualization method based on the OGC standard according to any one of claims 1 to 5, characterized in that: The system comprises: A dynamic attribute stream construction module is used to extend the time slots in the batch attribute table of OGC 3D Tiles, store the keyframe states of objects within a time window of preset length, and build a dynamic attribute stream in the time-enhanced 3D Tiles data layer; The state attribute extraction module, based on the dynamic attribute flow in the timing-enhanced 3D Tiles data layer, linearly interpolates the key frame state at the current time in the GPU shader to extract the state attributes of the key frame at the current time; The GPU execution acquisition module is used to obtain RDF / SPARQL business rules, convert RDF triples or SPARQL query conditions into logical expression trees, and extract results based on the state attributes of the current time key frame to obtain GPU executable instructions based on the current time key frame; The visual effects signal analysis module is used to calculate the dynamic interpolation position corresponding to the current time keyframe state attribute in the WebGPU rendering pipeline, perform business rule determination based on the GPU executable instructions of the current time keyframe, and output visual effects signals when the business rules are triggered; The timing slot key frame update module is used to generate a differential update package according to the rule trigger signal, and return the differential update package to the timing data layer to update the timing slot key frame.

7. The digital twin multidimensional data visualization system based on the OGC standard according to claim 6 is characterized in that: The GPU execution acquisition module includes a logic expression tree acquisition unit and an execution instruction analysis unit. The logical expression tree acquisition unit is used to acquire RDF / SPARQL business rules and convert RDF triples or SPARQL query conditions into a logical expression tree; The execution instruction analysis unit obtains a GPU executable instruction based on the current time key frame in combination with the state attribute extraction result of the current time key frame.

8. The digital twin multidimensional data visualization system based on the OGC standard according to claim 6, characterized in that: The visual special effect signal analysis module includes an interpolation position acquisition unit and a special effect signal output unit. The interpolation position acquisition unit is used to calculate the dynamic interpolation position corresponding to the current time key frame state attribute in the WebGPU rendering pipeline; The special effect signal output unit performs business rule determination based on the GPU executable instructions of the current time key frame, and outputs a visual special effect signal when the business rule is triggered.

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