Space-time object generation method and system based on workflow

Abstract

The invention relates to the technical field of geographic information systems, in particular to a space-time object generation method and system based on workflow, and the method comprises the steps: constructing a total framework of objectified description of multi-source geographic space data; designing a space-time object analytic expression method considering space-time object multivariate features; abstracting the space-time objects into different object classes according to the similarity of the features, and constructing a class template for each class of space-time objects for storing description contents and data conversion rules of the class of space-time objects; a space-time object generation process is split into a plurality of task nodes which are independent in function and loosely coupled in structure by adopting a workflow technology, a workflow oriented to multi-source geographic space data is constructed according to combination and execution logic of the task nodes, and meanwhile, instantiation of the space-time object is realized under the constraint of a class template and a data conversion rule. Generation of large-scale space-time object data is achieved based on the workflow technology, and the efficient and high-quality production requirements of space-time objects in a space information system are met.

Description

Technical Field

[0001] The present invention relates to the field of geographic information system technology, and in particular to a workflow-based spatiotemporal object generation method and system. Background Art

[0002] In the 60 years of development, the Geographic Information System (GIS) has gradually become an indispensable tool for expressing and analyzing the real world. As human beings' understanding of the real world gradually moves from the surface to the universe, from static to dynamic, and from independent individuals to related groups, the deepening of human beings' spatial cognition has become a barrier for GIS to express and analyze the real world. For this reason, Academician Zhou Chenghu proposed the concept of pan-spatial information system (PSIS pan-spatialinformation system), which expanded the spatial scale of the geographic information system to micro and macro space, expanded spatial data to spatiotemporal big data, and expanded spatial analysis to big data spatial analysis, and proposed to establish an omnipresent GIS world. Professor Hua Yixin proposed a multi-granular spatiotemporal object data model based on the pan-spatial information system, which provides a data model for the pan-spatial information system to express the dynamic and complex world from six aspects: spatial scope, dynamic changes, complex relationships, cognition and behavior, visualization technology, and spatiotemporal big data analysis. It has changed the traditional GIS method of mapping the geographic world with abstract spatial graphic elements, and created a new model of directly mapping the real world with spatiotemporal objects, which has changed the description, creation, storage, management and application of the real world by the spatial information system from the bottom model level.

[0003] Spatiotemporal objects break through the indirect modeling method of traditional GIS using map layers as templates. Unlike traditional surveying and mapping data production for specific spatiotemporal scales and themes, the generation of spatiotemporal objects requires multi-dimensional observation, abstract modeling and fusion processing of real-world objects or phenomena, thereby generating spatiotemporal object data with cross-spatiotemporal scales and multi-semantic association characteristics. The production of spatiotemporal object data has many links, long processes, and complex content, involving a large amount of human-computer collaboration and quality control. This is an important problem facing the current large-scale production of spatiotemporal object data. Traditional production uses data interactive editing or tool conversion methods, which has low data production efficiency and is difficult to standardize the production process. Summary of the invention

[0004] The present invention aims to solve the problems of low efficiency, low flexibility and difficulty in standardizing the production process of spatiotemporal object data. A workflow-based spatiotemporal object generation method and system are proposed, which abstracts each link of spatiotemporal object production into task nodes, drives the entire production process with the spatiotemporal object data flow, and solves the source problem of large-scale spatiotemporal object data.

[0005] To achieve the above purpose, the technical solution adopted is:

[0006] A method for generating spatiotemporal objects based on workflow, comprising the following contents:

[0007] According to the generation requirements of spatiotemporal object data, a general framework for object-oriented description of multi-source geospatial data is constructed;

[0008] According to the description of the above-mentioned spatiotemporal objects, a method for expressing the spatiotemporal objects in an analytical way is designed, which takes into account the semantics, scale, dimension, tense, autonomy, and multi-functionality of the spatiotemporal objects.

[0009] Abstract the spatiotemporal objects into different object classes according to the similarity of features, and construct a class template for each type of spatiotemporal object to save the description content and data conversion rules of the spatiotemporal object;

[0010] Workflow technology is used to split the generation process of spatiotemporal objects into several functionally independent and loosely coupled task nodes. According to the combination and execution logic of task nodes, a workflow for multi-source geospatial data is constructed. At the same time, under the constraints of class templates and data conversion rules, the instantiation of spatiotemporal objects is realized.

[0011] According to the workflow-based spatiotemporal object generation method of the present invention, further, the overall framework for constructing the object-oriented description of multi-source geospatial data includes spatiotemporal reference, spatial location, spatial form, attribute characteristics, behavioral capabilities and change sets;

[0012] Spatiotemporal reference: describes the time reference and spatial reference information of spatiotemporal objects;

[0013] Spatial position: describes the specific position and direction of a space-time object in different spatial reference systems;

[0014] Spatial morphology: describes the morphological characteristics and manifestations of space-time objects;

[0015] Attribute characteristics: describe the attribute information of spatiotemporal objects;

[0016] Behavioral capability: describes the ability of a spatiotemporal object to undergo state transitions caused by itself or external objects;

[0017] Change set: describes the change information of all characteristics of a spatiotemporal object, including spatiotemporal reference, spatial position, spatial form, attribute characteristics, and behavioral capabilities.

[0018] According to the workflow-based spatiotemporal object generation method of the present invention, further, a spatiotemporal object analytical expression method is designed to express spatiotemporal objects from six aspects: spatiotemporal reference, spatial position, spatial form, attribute characteristics, behavioral capabilities and change sets; wherein, the spatiotemporal reference includes time reference and space reference; the spatial position includes location data of different location types; the spatial form includes spatiotemporal object form and data object form; the attribute characteristics include attribute identifiers, attribute names and attribute value information; the behavioral capabilities are driven by the behavioral model and specifically supported by the computing model, and the computing model includes model types, model resource identifiers and input and output parameters; the change set is recorded and implemented through version technology and dynamic data flow, including change action identifiers, action types, action characteristics and action result information.

[0019] According to the workflow-based spatiotemporal object generation method of the present invention, further, the spatiotemporal object form has time and space characteristics, and directly uses its own geometric data for positioning; the data object form does not have clear time and space characteristics, and relies on the spatial position of the spatiotemporal object for positioning.

[0020] According to the workflow-based spatiotemporal object generation method of the present invention, further, constructing a class template for each type of spatiotemporal object includes:

[0021] In the process of creating the spatiotemporal object class template, the six-tuple feature is designed according to the characteristics and business requirements of the spatiotemporal object class. Specifically, the class template of this type of spatiotemporal object is obtained through personalized design of fields, time reference dictionary, space reference dictionary, location dictionary, morphological dictionary and behavior model.

[0022] Users create multiple class views for different scenarios according to different actual application requirements. Class templates are shared through references between different class views of the same user and between class views of different users.

[0023] According to the workflow-based spatiotemporal object generation method of the present invention, further, the generation process of the spatiotemporal object includes a data parsing module, an object encapsulation module, an iteration module and a logic control module; wherein the data parsing module is used to parse the source data and extract the information required to construct the six-tuple features of the spatiotemporal object; the object encapsulation module encapsulates the extracted six-tuple features into a spatiotemporal object under the constraints of the class template and the data conversion rules; the iteration module is used to traverse the data, and the iteration object is the source data or the generated spatiotemporal object; the logic control module is used to determine the logical order of execution between the various functional modules in the workflow;

[0024] According to the workflow framework, the spatiotemporal object generation process is first split into several task nodes with fine-grained functional modules, and then combined on demand based on the specific requirements of the user. A customized workflow is formed by splicing and combining task nodes. When constructing the workflow, the required existing task nodes are called first to realize functional reuse.

[0025] According to the workflow-based spatiotemporal object generation method of the present invention, the method further includes running debugging: visually running debugging of the generated spatiotemporal object, checking the information content and dynamic changes of the six-tuple features during the entire life cycle of the spatiotemporal object.

[0026] According to the workflow-based spatiotemporal object generation method of the present invention, further, the spatiotemporal object is published for application after running and debugging, and the spatiotemporal object that meets the quality requirements provides spatiotemporal object access to the outside through object-based data services.

[0027] Furthermore, the present invention also provides a workflow-based spatiotemporal object generation system, comprising:

[0028] The spatiotemporal object description module is used to construct a general framework for object-based description of multi-source geospatial data according to the generation requirements of spatiotemporal object data;

[0029] A spatiotemporal object expression module is used to design a spatiotemporal object analytical expression method that takes into account the semantics, scale, dimension, tense, autonomy, and multi-functionality of the spatiotemporal object according to the description content of the spatiotemporal object;

[0030] The class template design module is used to abstract the spatiotemporal objects into different object classes according to the similarity of features, and to construct a class template for each type of spatiotemporal object to store the description content and data conversion rules of the spatiotemporal object;

[0031] The spatiotemporal object instantiation module is used to split the generation process of spatiotemporal objects into several functionally independent and loosely coupled task nodes using workflow technology, and to build a workflow for multi-source geospatial data based on the combination and execution logic of task nodes. At the same time, it realizes the instantiation of spatiotemporal objects under the constraints of class templates and data conversion rules.

[0032] The beneficial effects achieved by adopting the above technical solution are:

[0033] 1. A methodological system that is conducive to improving the construction of spatiotemporal object data

[0034] Traditional spatiotemporal object data production adopts data interactive editing or tool conversion methods, which can realize the production of small batches of high-value spatiotemporal object data. The present invention standardizes spatiotemporal object data production into six steps: spatiotemporal object description, spatiotemporal object expression, object class template design, spatiotemporal object instantiation, operation and debugging, and application release. This technical system can complete the transformation of spatiotemporal object construction from manual to automated and then to customized and streamlined, thereby building a complete spatiotemporal object modeling method system.

[0035] 2. It is conducive to improving the efficiency of spatiotemporal object data construction

[0036] The present invention standardizes the technical process of spatiotemporal object data production. It can encapsulate the common knowledge and data rules of the same type of land objects or phenomena through object class templates according to actual task requirements, and realize the derivation and reuse of class templates through operations such as association, inheritance, and aggregation. On the basis of class templates, multi-source heterogeneous spatiotemporal data with different characteristics are integrated and fused, and the full life cycle modeling of spatiotemporal objects is realized by using change sets, which effectively solves the contradiction between flexibility and standardization in the process of spatiotemporal object data modeling, improves the reuse efficiency of knowledge and rules in the process of spatiotemporal object data construction, and improves the efficiency of spatiotemporal object data construction.

[0037] 3. It is conducive to achieving efficient human-machine collaboration and data quality control in the production process of spatiotemporal object data

[0038] The production of spatiotemporal object data has many links, long processes, and complex contents, involving a large amount of human-machine collaboration and quality control, which is an important problem facing the current large-scale production of spatiotemporal object data. The workflow-based spatiotemporal object data generation method proposed in this invention abstracts each link of spatiotemporal object production into task nodes, drives the entire production process with spatiotemporal object data flow, and adds operation debugging and application release links, which not only enhances the reusability of software functions, but also releases human resources and improves data quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings of the embodiments of the present invention, wherein the drawings are only used to illustrate some embodiments of the present invention, but not to limit all embodiments of the present invention thereto.

[0040] Figure 1 is a flowchart of a method for generating a spatiotemporal object based on a workflow according to an embodiment of the present invention;

[0041] Figure 2 is a schematic diagram of describing a spatiotemporal object according to an embodiment of the present invention;

[0042] Figure 3 is a schematic diagram of the spatiotemporal object expression of an embodiment of the present invention;

[0043] Figure 4 is a schematic diagram of the structure of a class template design tool system according to an embodiment of the present invention;

[0044] Figure 5 It is a diagram of the operation mechanism of generating spatiotemporal objects based on workflow in an embodiment of the present invention;

[0045] Figure 6 is a workflow-based spatiotemporal object generation step diagram of an embodiment of the present invention;

[0046] Figure 7 This is an example diagram of a workflow for generating spatiotemporal objects of vector map data according to an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings of specific embodiments of the present invention to clearly and completely describe the exemplary scheme of the embodiment of the present invention. Unless otherwise defined, the technical terms or scientific terms used in the present invention should be the common meanings understood by people with ordinary skills in the field.

[0048] like Figure 1 As shown, this embodiment discloses a method for generating spatiotemporal objects based on a workflow, comprising the following steps:

[0049] Step S101: construct a general framework for object-oriented description of multi-source geographic spatial data according to the generation requirements of spatiotemporal object data.

[0050] Spatiotemporal objects have the characteristics of multi-granularity, multi-type, multi-form, multi-level, multi-functional autonomy, time-series changes, and carrying structured, semi-structured and unstructured data. In order to build a spatiotemporal object data model, it is necessary to standardize the description of spatiotemporal objects. Considering the requirements of subsequent object unified expression, full life cycle management, behavioral capability execution, multi-form unified description, and multi-reference seamless crossing, it is necessary to describe them from six aspects: spatiotemporal reference, spatial position, spatial form, attribute characteristics, behavioral capability, and change set. Figure 2 shown.

[0051] Time reference: Time reference and space reference information used to accurately describe space-time objects. Time reference includes time reference and space reference. Two time reference systems are usually required: a main reference system, such as Beijing time, which is used for the unified description of the time characteristics of multiple space-time objects; a self-reference system, such as the time when the object is generated, which is used to describe the time characteristics of the space-time object itself. Each space-time object usually requires three spatial reference systems: a main reference system, which is used to describe the spatial position of the space-time object in the entire spatial scene, such as describing the position of a building based on a certain general coordinate system (CGCS2000); a parent reference system, which is used to describe the spatial position of the space-time object in the parent object; and a self-reference system, which is used to describe the spatial position of the child object of the space-time object.

[0052] Spatial position: used to describe the specific position and direction of a space-time object in different spatial reference systems. When describing the spatial position of a space-time object, the coordinate value of its self-reference system origin in other reference systems such as the parent reference system can be used as the spatial position data. However, it is not enough to describe the spatial position with only one three-dimensional coordinate (X, Y, Z). It is also necessary to describe the directional relationship between the space-time object's self-reference system and the parent reference system.

[0053] Spatial morphology: describes the morphological characteristics and forms of expression of space-time objects. In the real world, space-time objects are composed of solid, liquid, gaseous, field and other forms of matter to form different things and phenomena, and have different visual expressions at different times, scales, scenes and applications. The same space-time object often requires the use of multiple data and models to describe different aspects (such as different directions, different themes, different angles, etc.), different precisions (such as overview, detail, abstraction, etc.), and different forms (two-dimensional, three-dimensional, imaging, modeling, etc.). For example, a block needs to use planar position data of different precisions and times, multi-directional photographic images, multiple types of remote sensing images, and three-dimensional models of the block to describe its morphology.

[0054] Attribute characteristics: Describes the attribute information of spatiotemporal objects. Attribute information refers to the category, quantity, quality, name, etc. of things or phenomena. Different from the traditional GIS map feature description method, spatiotemporal objects can carry and describe more detailed, complex, and high-dimensional attribute characteristic information in the real world. All attribute characteristics of spatiotemporal objects will change dynamically.

[0055] Behavioral ability: describes the state change ability of a space-time object caused by itself or external objects (including the external environment). It is also the performance (action) of a space-time object under internal laws and external interference over time. Internal laws refer to the rules followed by objects in space-time scenes, such as their own physical properties, and external interference refers to various external interference factors, including the natural laws of the external environment (gravity, wind, temperature, interaction between objects, etc.) and stimulation from other space-time objects.

[0056] Change set: describes the change information of all characteristics of a spatiotemporal object. Spatiotemporal objects have the characteristics of temporal changes. Within the life cycle of an object, all characteristics of the object may change, such as attribute changes, position changes, etc. However, the frequency of characteristic changes can be fast or slow. For example, the characteristics of a mountain will basically not change; the shape of a city will change slowly with the urbanization process; the trajectory of a car will change frequently, and so on.

[0057] Step S102: Based on the description of the spatiotemporal object in step S101, a method for expressing the spatiotemporal object in an analytical manner is designed that takes into account the multiple characteristics of the spatiotemporal object, such as semantics, scale, dimension, tense, autonomy, and versatility. The spatiotemporal object is expressed from six aspects: spatiotemporal reference, spatial position, spatial form, attribute characteristics, behavioral ability, and change set, laying a foundation for the design of the spatiotemporal object data structure, and the storage and management of data. Figure 3 shown.

[0058] The spatiotemporal object reference includes time reference and space reference. Different spatiotemporal objects can have different spatiotemporal references, which can be converted at the application level according to the conversion tool. Spatial position is used to express the geometric position information of spatiotemporal objects, including position data of different position types. Spatial morphology is used to express the morphological set of spatiotemporal objects. The morphological types here include spatiotemporal object morphology and data object morphology. Spatiotemporal object morphology (such as geometric elements, point clouds, images, etc.) has temporal and spatial characteristics and directly uses its own geometric data for positioning; data object morphology (such as text, video, model, etc.) does not have clear spatial and temporal characteristics and needs to rely on the spatial position of spatiotemporal objects for positioning. Spatiotemporal object morphology and data object morphology are both the smallest units of spatiotemporal objects. Attribute features are used to express the attribute information of spatiotemporal objects. Attribute features include attribute identifiers, attribute names, and attribute value information. Behavioral capabilities are used to express the performance (action) of spatiotemporal objects under internal laws and external interference. They are driven by behavioral models and supported by computational models. Computational models include types, model resource identifiers, input and output parameters, etc. The change set is used to express the change process and change information of the spatiotemporal object throughout its life cycle. It is recorded and implemented through version technology and dynamic data streams, including information such as the change ID, action type, action characteristics, and action results.

[0059] Step S103: abstract the spatiotemporal objects into different object classes according to the similarity of features, and construct a class template for each class of spatiotemporal objects to store the description content and data conversion rules of the six-tuple of the spatiotemporal objects of this class. Object class templates can be associated, inherited and aggregated, and are uniformly managed by the object class template pool.

[0060] The design of spatiotemporal object classes is the key to creating spatiotemporal objects in object-oriented modeling. Using object-oriented thinking, spatiotemporal objects with the same or similar characteristics in the real world are abstracted into different object classes. A class template is built for each type of spatiotemporal object to save the description content and rules of the six-tuple characteristics of this type of object. The object class template is a constraint on the instantiation of the same type of spatiotemporal objects.

[0061] When constructing the class template, a class template design tool is used. This tool can realize object-oriented spatiotemporal modeling, making the design of spatiotemporal object class templates as simple and intuitive as object-oriented programming. The tool supports interactive visual dragging, and supports concepts such as inheritance, association, combination, and aggregation in UML design. The design of spatiotemporal object class templates is completed through the logical organization of concepts such as fields, time reference dictionaries, space reference dictionaries, location dictionaries, morphological dictionaries, and behavior models. Its system structure is as follows Figure 4 shown.

[0062] Class view is the logical organization of spatiotemporal object classes in the same scenario. Users can create multiple class views for different scenarios according to different actual application requirements. Class templates can be shared through references between different class views of the same user and between class views of different users. For example, user B finds through search that spatiotemporal object class A has been created and meets his business needs. At this time, he can add spatiotemporal object class A to his class view through interactive visual dragging.

[0063] In the process of creating the spatiotemporal object class template, its six-tuple features are designed according to the characteristics and business needs of the spatiotemporal object class, such as selecting the default spatiotemporal reference from the spatial reference dictionary and the temporal reference dictionary {for example, the default spatial reference is CGCS2000 (China Geodetic Coordinate System 2000), and the default temporal reference is UTC (Coordinated Universal Time)}, designing different types of fields to add to the attribute features, developing a behavioral model library and associating it with behavioral capabilities, etc., and finally establishing a collection of spatiotemporal object class templates that meet different application needs.

[0064] Step S104, using workflow technology to split the generation process of spatiotemporal objects into several functionally independent and loosely coupled task nodes, constructing a workflow for multi-source geospatial data based on the combination and execution logic of the task nodes, and realizing the instantiation of spatiotemporal objects under the constraints of class templates and data conversion rules in the class template pool.

[0065] Workflow technology is used to split a task that can be described as a process-based work into several task nodes. Each task node exists independently and assumes its own business function. There is no strict order between them. Based on the specific requirements of the user, it is combined on demand to form a customized workflow through the splicing and combination of task nodes. Compared with the traditional generation method, the decoupling of various modules can be achieved. The process of generating spatiotemporal objects based on workflow is more fine-grained, which is impossible to achieve with traditional generation methods. Users only need to complete the combination of tools, the construction of process instances, and the input of source data in the conversion process, and they can quickly and conveniently produce spatiotemporal objects through customized business processes.

[0066] The workflow-based spatiotemporal object generation method includes a data parsing module, an object encapsulation module, an iteration module and a logic control module. The data parsing module is used to parse the source data and extract the information required to construct the six-tuple features of the spatiotemporal object. The object encapsulation module encapsulates the extracted six-tuple features into spatiotemporal objects under the constraints of the class template and data conversion rules, and the data format meets the storage standards. The iteration module is used to traverse the data. The iteration object can be the source data or the generated spatiotemporal object. It can speed up the generation of spatiotemporal objects from the same type of source data and realize the batch construction of spatiotemporal objects. The logic control module is used to determine the logical order of execution between the various functional modules in the workflow. The connecting line with arrows is the most commonly used method to determine the module processing order. In addition, there are logical operations such as logical AND and logical OR. Its operating mechanism is as follows: Figure 5 shown.

[0067] The following uses the vector map data source as an example to introduce the workflow generation method of spatiotemporal objects.

[0068] (4.1) Construction of task nodes for generating spatiotemporal objects of vector map data

[0069] In view of the complex structure and large number of categories of vector map data, the data conversion process is decomposed into tasks to make them different task nodes in the workflow, and they are reorganized on demand and in sequence to achieve process reuse. The workflow engine parses, manages and executes the created process instances based on the business process modeling specifications. Its main components are deployed in a distributed manner and can run simultaneously on multiple terminals to achieve multi-user collaborative development. Figure 6 As shown, under the workflow engine framework, the functionally independent steps in the data conversion process are split into different task nodes under the constraints of modeling specifications, and the creation of the spatiotemporal object generation workflow is completed through the combination and reuse of nodes.

[0070] (4.2) Construction of spatiotemporal object generation workflow for vector map data based on BPMN rules.

[0071] BPMN (Business Process Modeling Notation) is a widely used modeling language that follows the established business modeling logic and rules. It achieves a graphical description of business processes by drawing flowcharts, thereby achieving good visual effects. BPMN process modeling symbols are diverse and powerful. This solution uses BPMN symbols as the specification for workflow construction. The relevant process modeling symbols can be mainly divided into the following four categories: events, tasks, gateways, and sequence flows. The detailed definitions are as follows:

[0072] (1) Event: It is a modeling symbol that marks the start, end and pause of the process model. It can contain multiple event symbols according to the specific business process needs.

[0073] (2) Task: A task is the basic unit for executing specific business functions. It cannot be further subdivided according to the specific functions assigned to it by the business and is the core node of process construction.

[0074] (3) Gateway: The gateway contains the execution logic of the process and is usually connected to the task combination so that the tasks are executed in a certain logical order under the action of the internal logic of the gateway.

[0075] (4) Sequence flow: It is a directional expression of the business process, used to describe the direction of process execution and data flow. It is a necessary connection symbol between events, tasks, and gateways.

[0076] The spatiotemporal object generation workflow of vector map data is composed of a variety of symbols, including start and end symbols, data flow, logical branches and functional nodes. In order to realize the model construction of the spatiotemporal object generation process, the spatiotemporal object generation process modeling symbols are introduced in detail, as shown in Table 1.

[0077] Table 1 BPMN modeling rule graphic elements

[0078]

[0079] The meanings of the graphic elements in the table are as follows:

[0080] (1) Start event: The start event is the starting symbol of a business process. Any process must start with the start event to run the process instance. Depending on the specific process instance, it can contain one or more start events.

[0081] (2) End event: The end event is the termination symbol of the business process, which prevents the migration function node from being unable to end after processing.

[0082] (3) Service Task: A service task is a common graphic element that is carried out in a business sequence. It is the basic unit that constitutes the business by connecting the graphic element with the actual business function through the development of business code.

[0083] (4) User tasks: These are processes that must be completed manually during the process creation process. After manual processing, the process instances can be executed sequentially.

[0084] (5) Script task: A script task is an automatic activity. When the sequence flow flows to the script task, the script attached to it runs automatically.

[0085] (6) Parallel Gateway: Parallel gateway can aggregate multiple sequence flows and also branch out multiple sequence flows. When a sequence flow flows in, the parallel gateway can only continue to execute after all sequence flows have been aggregated; when a sequence flow flows out, each branch is executed simultaneously.

[0086] (7) Exclusive gateway: The exclusive gateway continues to execute after summarizing the input sequence flow, and makes judgments one by one based on the judgment conditions of multiple branches. The sequence flow output of the exclusive gateway can only have one output node. The branch that passes the first judgment condition is the only execution path of the exclusive gateway.

[0087] (8) Inclusive gateway: The inclusive gateway is a combination of a parallel gateway and an exclusive gateway. It is used to aggregate multiple paths of parallel tasks during the input process. During output, it can select the next node that meets the conditions according to the judgment method, and can also run multiple branches in parallel, thus realizing the parallel execution of multiple paths that meet the conditions.

[0088] (9) Sequence flow: Sequence flow is the only way to connect each graphic element and realize the transmission of data flow. It is the relationship between the functional nodes behind the graphic elements that are executed in sequence and cyclically.

[0089] Taking the generation of spatiotemporal objects of vector map data as an example, the workflow constructed in a graphical interactive way using BMPN modeling symbols is as follows: Figure 7 The task node names and task node functions are shown in Table 2.

[0090] Table 2 Task node names and task node function correspondence table

[0091] Task node name Task node function ShpParser Shp file parser VectorGenerator Vector feature generator STObjectGenerator Spatiotemporal Object Generator VectorFieldsGenerator Mapping Set Generator STOWriter Spatiotemporal Object Writer

[0092] (4.3) Vector map data spatiotemporal object generation workflow release

[0093] The workflow and task node functional services built in a graphical interactive manner are sent to the workflow engine in XML format using the BPMN language. The workflow engine is responsible for the parsing, execution, and management of process files on the server side using the BPMN standard.

[0094] (4.4) Vector map data spatiotemporal object generation workflow operation

[0095] After the workflow is sent to the server, the workflow engine can host the workflow and view all published workflows in the server workflow management page. When the front-end user clicks to run the workflow, the workflow engine's running interface will be called. The workflow engine starts the relevant workflow execution instance and generates spatiotemporal object data from the vector map data under the constraints of the object class template and conversion rules. At the same time, the workflow engine can also monitor the execution status of the workflow and return the current execution status. The front-end system can display the currently executed workflow task node in a highlighted mode to facilitate user status tracking.

[0096] Step S104: Run and debug. Perform visual run and debug (quality check) on the generated spatiotemporal object, check the information content and dynamic changes of the six-tuple features during the entire life cycle of the spatiotemporal object, and ensure the integrity and logical consistency of the data.

[0097] During the entire life cycle of the generation, change, and development of space-time objects, their space-time reference, spatial position, spatial form, attribute characteristics, behavioral capabilities and other characteristics may change. Therefore, it is necessary to run and debug the generated space-time object data (quality inspection). The main method of visual inspection is to use the timeline as the controller to display the status of the space-time object at different times, and use the visual expression method of map + chart to fully display the change set information contained in the entire life cycle of the space-time object to ensure the integrity and logical consistency of the data.

[0098] Step S105: Publish the application. The spatiotemporal object data that meets the quality requirements is provided with unified spatiotemporal object access through object-based data services to meet the application needs of object data in various industries and fields.

[0099] The present invention breaks through the mode of organizing spatial data with "layer-element-attribute" in the original geographic information system, and directly adopts spatiotemporal objects to describe the landforms and phenomena in the real world. It needs to manage the entire space from indoor space to outer space and the entire life cycle from the past to the future; it needs to manage information content covering multiple characteristics such as time, space, attributes, and relationships; it needs to achieve integrated access and high-performance retrieval of spatiotemporal objects. Therefore, different from the service mode of traditional geographic spatial data, the present invention provides object-oriented access capability for spatiotemporal object data, and uses a unified object data structure on the Web and desktop ends to provide six-tuple feature access to spatiotemporal objects, meeting the application needs of object data in various industries and fields.

[0100] Corresponding to the above method, this embodiment also proposes a workflow-based spatiotemporal object generation system, comprising:

[0101] The spatiotemporal object description module is used to construct a general framework for object-based description of multi-source geospatial data based on the generation requirements of spatiotemporal object data.

[0102] The spatiotemporal object expression module is used to design a spatiotemporal object analytical expression method that takes into account the semantics, scale, dimension, tense, autonomy, and multi-functional and multi-dimensional characteristics of the spatiotemporal object based on the description content of the above-mentioned spatiotemporal object.

[0103] The class template design module is used to abstract spatiotemporal objects into different object classes according to the similarity of features, and to construct a class template for each type of spatiotemporal object to save the description content and data conversion rules of the spatiotemporal object.

[0104] The spatiotemporal object instantiation module is used to split the generation process of spatiotemporal objects into several functionally independent and loosely coupled task nodes using workflow technology, and to build a workflow for multi-source geospatial data based on the combination and execution logic of task nodes. At the same time, it realizes the instantiation of spatiotemporal objects under the constraints of class templates and data conversion rules.

[0105] Unless otherwise specifically stated, the components, steps, numerical expressions and values ​​set forth in these embodiments do not limit the scope of the present invention.

[0106] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0107] The units and method steps of each example described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. A person of ordinary skill in the art may use different methods to implement the described functions for each specific application, but such implementation is not considered to be beyond the scope of the present invention.

[0108] Those skilled in the art will appreciate that all or part of the steps in the above method can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, such as a read-only memory, a disk or an optical disk. Optionally, all or part of the steps in the above embodiment can also be implemented using one or more integrated circuits, and accordingly, each module / unit in the above embodiment can be implemented in the form of hardware or in the form of software function modules. The present invention is not limited to any specific form of combination of hardware and software.

[0109] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed by the present invention, or replace some of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for generating spatiotemporal objects based on workflow, characterized in that: Contains the following: According to the generation requirements of spatiotemporal object data, a general framework for object-oriented description of multi-source geospatial data is constructed; According to the description of the above-mentioned spatiotemporal objects, a method for expressing the spatiotemporal objects in an analytical way is designed, which takes into account the semantics, scale, dimension, tense, autonomy, and multi-functionality of the spatiotemporal objects. Abstract the spatiotemporal objects into different object classes according to the similarity of features, and construct a class template for each type of spatiotemporal object to save the description content and data conversion rules of the spatiotemporal object; Workflow technology is used to split the generation process of spatiotemporal objects into several functionally independent and loosely coupled task nodes. According to the combination and execution logic of task nodes, a workflow for multi-source geospatial data is constructed. At the same time, under the constraints of class templates and data conversion rules, the instantiation of spatiotemporal objects is realized.

2. The workflow-based spatiotemporal object generation method according to claim 1, characterized in that: The overall framework for constructing object-oriented descriptions of multi-source geospatial data includes spatiotemporal references, spatial locations, spatial forms, attribute characteristics, behavioral capabilities, and change sets; Spatiotemporal reference: describes the time reference and spatial reference information of spatiotemporal objects; Spatial position: describes the specific position and direction of a space-time object in different spatial reference systems; Spatial morphology: describes the morphological characteristics and manifestations of space-time objects; Attribute characteristics: describe the attribute information of spatiotemporal objects; Behavioral capability: describes the ability of a spatiotemporal object to undergo state transitions caused by itself or external objects; Change set: describes the change information of all characteristics of a spatiotemporal object, including spatiotemporal reference, spatial position, spatial form, attribute characteristics, and behavioral capabilities.

3. The workflow-based spatiotemporal object generation method according to claim 1, characterized in that: The analytical expression method of designing spatiotemporal objects is used to express spatiotemporal objects from six aspects: spatiotemporal reference, spatial position, spatial form, attribute characteristics, behavioral capabilities and change sets. Among them, the spatiotemporal reference includes time reference and space reference; the spatial position includes location data of different location types; the spatial form includes spatiotemporal object form and data object form; the attribute characteristics include attribute identification, attribute name and attribute value information; the behavioral capability is driven by the behavioral model and is specifically supported by the computing model, which includes model type, model resource identification and input and output parameters; the change set is recorded and implemented through version technology and dynamic data flow, including change action identification, action type, action characteristics and action result information.

4. The workflow-based spatiotemporal object generation method according to claim 3, characterized in that: The spatiotemporal object form has temporal and spatial characteristics and directly uses its own geometric data for positioning; the data object form does not have clear temporal and spatial characteristics and relies on the spatial position of the spatiotemporal object for positioning.

5. The workflow-based spatiotemporal object generation method according to claim 2, characterized in that: Constructing a class template for each type of spatiotemporal object includes: In the process of creating the spatiotemporal object class template, the six-tuple feature is designed according to the characteristics and business requirements of the spatiotemporal object class. Specifically, the class template of this type of spatiotemporal object is obtained through personalized design of fields, time reference dictionary, space reference dictionary, location dictionary, morphological dictionary and behavior model. Users create multiple class views for different scenarios according to different actual application requirements. Class templates are shared through references between different class views of the same user and between class views of different users.

6. The workflow-based spatiotemporal object generation method according to claim 1, characterized in that: The generation process of spatiotemporal objects includes a data parsing module, an object encapsulation module, an iteration module and a logic control module; the data parsing module is used to parse the source data and extract the information required to construct the six-tuple features of the spatiotemporal object; the object encapsulation module encapsulates the extracted six-tuple features into spatiotemporal objects under the constraints of the class template and data conversion rules; the iteration module is used to traverse the data, and the iteration object is the source data or the generated spatiotemporal object; the logic control module is used to determine the logical order of execution between the various functional modules in the workflow; According to the workflow framework, the spatiotemporal object generation process is first split into several task nodes with fine-grained functional modules, and then combined on demand based on the specific requirements of the user. A customized workflow is formed by splicing and combining task nodes. When constructing the workflow, the required existing task nodes are called first to realize functional reuse.

7. The workflow-based spatiotemporal object generation method according to claim 1, characterized in that: The method also includes running debugging: visually running debugging of the generated spatiotemporal object, and checking the information content and dynamic changes of the six-tuple features during the entire life cycle of the spatiotemporal object.

8. The workflow-based spatiotemporal object generation method according to claim 7, characterized in that: After running and debugging, the spatiotemporal objects are published and applied. The spatiotemporal objects that meet the quality requirements provide external spatiotemporal object access through objectized data services.

9. A workflow-based spatiotemporal object generation system, characterized in that: Include: The spatiotemporal object description module is used to construct a general framework for object-based description of multi-source geospatial data according to the generation requirements of spatiotemporal object data; A spatiotemporal object expression module is used to design a spatiotemporal object analytical expression method that takes into account the semantics, scale, dimension, tense, autonomy, and multi-functionality of the spatiotemporal object according to the description content of the spatiotemporal object; The class template design module is used to abstract the spatiotemporal objects into different object classes according to the similarity of features, and to construct a class template for each type of spatiotemporal object to store the description content and data conversion rules of the spatiotemporal object; The spatiotemporal object instantiation module is used to split the generation process of spatiotemporal objects into several functionally independent and loosely coupled task nodes using workflow technology, and to build a workflow for multi-source geospatial data based on the combination and execution logic of task nodes. At the same time, it realizes the instantiation of spatiotemporal objects under the constraints of class templates and data conversion rules.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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