A blockchain-based evidence storage method and apparatus for medical data operation features

Abstract

This invention relates to a blockchain-based method and apparatus for storing medical data operation features. The method includes: real-time monitoring of medical data operations performed by a user on a portal webpage provided by a medical data sharing network to obtain user monitoring data; extracting operation features based on the user's private information and the user monitoring data to obtain operation feature data; obtaining a blockchain timestamp from the storage blockchain as the operation time; and composing private data from the operation feature data and the operation time; generating a zero-knowledge proof π based on the private data using zero-knowledge proof technology and sending it to the storage blockchain for verification to obtain a corresponding verification result; generating an electronic fingerprint based on the private data when verification is successful, and storing the electronic fingerprint on the blockchain using an asynchronous processing method with a cache queue; and performing medical data operations based on the user monitoring data after successful storage. This invention can improve the data's anti-tampering capability and proactive backup capability.

Description

Technical Field

[0001] This invention relates to the field of data processing technology, and in particular to a blockchain-based method and apparatus for storing medical data operation features. Background Technology

[0002] In conventional medical data sharing networks, the recording of user data access / operation behavior largely relies on log / event service mechanisms. However, typical log / event services usually use traditional databases for data storage. Based on practical experience, this traditional method performs poorly in terms of data tamper prevention and proactive backup capabilities, posing a risk of data alteration or loss, and making it difficult to ensure the integrity and reliability of data records. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a blockchain-based method, apparatus, electronic device, and computer-readable storage medium for storing medical data operation features. This invention monitors in real-time the medical data operations performed by users on a portal webpage provided by a medical data sharing network to obtain corresponding user monitoring data; extracts operation features based on the current user's private information and user monitoring data to obtain corresponding operation feature data; obtains a blockchain timestamp from the storage blockchain as the corresponding operation time; and combines the operation feature data and operation time to form corresponding private data. Using zero-knowledge proof technology, a zero-knowledge proof π is generated based on the private data and sent to the storage blockchain for verification to obtain the corresponding verification result. If the verification result is successful, an electronic fingerprint is generated based on the private data to obtain corresponding electronic fingerprint data; the electronic fingerprint data is then stored on the blockchain using an asynchronous processing method with a cache queue; and after successful storage, medical data operations are performed based on the user monitoring data, and the operation results are fed back to the current user. This invention uses a blockchain with a distributed ledger service to record and document users' data access / operation behavior. It can improve the anti-tampering capability of data through blockchain technology and enhance the proactive backup capability of data through the characteristics of the distributed ledger network.

[0004] To achieve the above objectives, a first aspect of the present invention provides a blockchain-based method for storing medical data operation features, the method comprising:

[0005] The client monitors user actions on a portal webpage provided by the medical data sharing network in real time to obtain corresponding user monitoring data. This user monitoring data includes an object identifier, operation type, and operation data. The object identifier is the routing path of the medical data object currently being operated on by the user. The routing path consists of a routing prefix and an end routing identifier, and corresponds to a specific data storage location on the medical data sharing network. The operation type includes at least add, modify, delete, and download. When the operation type is add or modify, the operation data is one medical data object. When the operation type is delete or download, the operation data is empty.

[0006] Based on the current user's private information and the user monitoring data, operation feature data is extracted to obtain corresponding operation feature data; a blockchain timestamp is obtained from the evidence storage blockchain as the corresponding operation time; and the operation feature data and the operation time are combined to form corresponding private data; the operation feature data includes the user's private key, the object identifier, and the operation type.

[0007] Using zero-knowledge proof technology, a zero-knowledge proof π is generated based on the private data and sent to the evidence storage blockchain for verification to obtain the corresponding verification result.

[0008] When the verification result is successful, electronic fingerprint data is generated based on the private data; the electronic fingerprint data is then stored on the blockchain using an asynchronous processing method through a cache queue; and after successful storage, medical data operations are performed based on the user monitoring data, and the operation results are fed back to the current user.

[0009] Preferably, the method further includes:

[0010] The medical data sharing network is a distributed data sharing network composed of multiple first network nodes. Each first network node corresponds to a node type, which includes at least a portal website node, a data storage node, and a data computing node. The first network node of the portal website node type is used to provide access services to the portal webpage. The first network node of the data storage node type is used to store the medical data objects. The first network node of the data computing node type is used to provide data storage services, data encryption and decryption services, and algorithm / model inference services.

[0011] The node network of the evidence storage blockchain is a distributed node network composed of multiple first network nodes of the data computing node type in the medical data sharing network. The distributed node network is deployed with distributed ledger service based on blockchain technology. All first network nodes of the blockchain network jointly maintain a feature evidence storage ledger based on blockchain technology, and all first network nodes have a complete copy of the ledger. All first network nodes on the evidence storage blockchain maintain full-chain time synchronization through an external time synchronization server.

[0012] When constructing the evidence storage blockchain, the first network nodes in the medical data sharing network whose node type is a data computing node are recorded as the corresponding first candidate nodes; and the importance parameter W of each first candidate node is initialized based on security index A, accessibility index B, throughput index C, and real-time index D; and the PageRank algorithm is used to iterate on all the importance parameters W multiple times until the absolute difference between the two most recent iterations of all the importance parameters W does not exceed a preset first threshold; and the first candidate nodes are sorted in descending order of importance parameter W to form a corresponding first node sequence; and the first K first candidate nodes in the first node sequence form the evidence storage blockchain; the security index A, the accessibility index B, the throughput index C, and the real-time index D are each a normalized numerical index; the initialized importance parameter W = w1A + w2B + w3C + w4D, where w1, w2, w3, and w4 are four preset weight parameters.

[0013] Preferably, the step of extracting corresponding operation feature data based on the current user's private information and the user monitoring data specifically includes:

[0014] The client consists of the current user's private key, the object identifier of the user monitoring data, and the operation type, forming the corresponding operation feature data.

[0015] Preferably, obtaining the blockchain timestamp from the evidence storage blockchain as the corresponding operation time specifically includes:

[0016] The client identifies the first network node on the evidence storage blockchain that is closest to the current user as the corresponding current time synchronization node; sends a first time synchronization request to the current time synchronization node; and uses the first timestamp sent back by the current time synchronization node as the corresponding operation time.

[0017] Preferably, the zero-knowledge proof technology generates a zero-knowledge proof π based on the private data and sends it to the evidence storage blockchain for verification to obtain the corresponding verification result, specifically including:

[0018] Step 51: The client generates a shared first CRS for the current user and the evidence storage blockchain according to the public reference string (CRS) generation method of zk-SNARKs zero-knowledge proof technology;

[0019] Step 52: According to the arithmetic circuit configuration method of zk-SNARKs zero-knowledge proof technology, generate a shared first arithmetic circuit for the current user and the evidence storage blockchain based on the preset permission verification rules;

[0020] The permission verification rules include operation type verification rules and operation time verification rules. The operation type verification rule consists of multiple object-permission mapping relationships. Each object-permission mapping relationship consists of a route identifier prefix and a type of operation permission. The types of operation permissions include add permission, modify permission, delete permission, and download permission. The permission values ​​for each type of operation permission include allow and prohibit. The operation time verification rule stipulates that the time interval between the current time and the operation time cannot exceed a preset time interval threshold.

[0021] The inputs to the first arithmetic circuit are the object identifier prefix d, the object operation type s, the object operation time t, and the current time t. now The output is the verification result r; the verification result r is 0 or 1, where 0 indicates verification failure and 1 indicates verification success.

[0022] The processing logic of the first arithmetic circuit is as follows: if the object identifier prefix d and the object operation type s satisfy one type of object-permission correspondence in the operation type verification rules, then the first result is set to 1; if the object identifier prefix d and the object operation type s do not satisfy any type of object-permission correspondence in the operation type verification rules, then the first result is set to 0; if the current time t now If the absolute time difference between the current time t and the object operation time t does not exceed the time interval threshold, then the second result is set to 1. now If the absolute time difference between the object operation time t and the time interval threshold exceeds the time interval threshold, the second result is set to 0; and the product of the first and second results is used as the corresponding verification result r.

[0023] Step 53: Extract the corresponding user private key, object identifier, operation type, and operation time from the private data;

[0024] Step 54: Use the routing identifier prefix of the object identifier as the corresponding object identifier prefix d; use the operation type as the corresponding object operation type s; use the operation time as the corresponding object operation time t; and use the current time information as the corresponding current time t. now The obtained object identifier prefix d, object operation type s, object operation time t, and current time t are then used to further define the object identifier prefix d, object operation type s, object operation time t, and current time t. now The input is processed by the first arithmetic circuit to obtain the corresponding verification result r;

[0025] Step 55: If the verification result r obtained this time is 1, then the process data of the first arithmetic circuit in this processing is extracted to form the corresponding first evidence according to the zero-knowledge evidence acquisition method of zk-SNARKs zero-knowledge proof technology; and the first evidence is hashed according to the zero-knowledge commitment generation method of zk-SNARKs zero-knowledge proof technology, and the calculation result is used as the corresponding first commitment; and the first evidence is signed based on the user's private key to obtain the corresponding first signature; and the user's public key corresponding to the user's private key is used as the corresponding first public key; and the zero-knowledge proof π composed of the first public key, the first commitment, the first evidence and the first signature is sent to the evidence storage blockchain; and the zero-knowledge proof verification result sent back by the evidence storage blockchain is used as the corresponding verification result.

[0026] Preferably, the method further includes:

[0027] The evidence storage blockchain extracts the corresponding first public key, first commitment, first evidence, and first signature from the zero-knowledge proof π;

[0028] The first signature is verified based on the first public key and the first evidence; and if the verification passes, the first comparison result is set to match; if the verification fails, the first comparison result is set to mismatch.

[0029] The first evidence is hashed according to the zero-knowledge commitment generation method of zk-SNARKs zero-knowledge proof technology, and the calculation result is used as the corresponding second commitment. The first and second commitments are identified as matching. If they match, the second comparison result is set as matching. If they do not match, the second comparison result is set as not matching.

[0030] The first evidence is loaded as process data onto the shared first arithmetic circuit for further processing to obtain a new verification result r; and the verification result r obtained this time is identified as 1. If it is, the third comparison result is set as a match; otherwise, the third comparison result is set as a mismatch.

[0031] The system identifies whether the first, second, and third comparison results are all matches; if so, it sets the corresponding zero-knowledge proof verification result as verified successfully; if not, it sets the corresponding zero-knowledge proof verification result as verified unsuccessfully; and sends the obtained zero-knowledge proof verification result back to the client.

[0032] Preferably, the step of generating electronic fingerprint data based on the private data specifically includes:

[0033] The client extracts the corresponding user private key and object identifier from the private data; and performs digest calculations on the user private key and object identifier based on the national cryptographic SM3 algorithm to obtain corresponding private key digests and identifier digests; then concatenates the private key and identifier digests in sequence to form a corresponding concatenated digest; and performs two digest calculations on the concatenated digest based on the national cryptographic SM3 algorithm to obtain corresponding first and second digests; and then concatenates the first and second digests in sequence to form the corresponding electronic fingerprint data;

[0034] The private key digest, the identifier digest, the first digest, and the second digest are all 128-bit digital digests; the concatenated digest and the electronic fingerprint data are all 256-bit digital digests.

[0035] Preferably, the asynchronous processing of the electronic fingerprint data through a cache queue for on-chain evidence storage specifically includes:

[0036] Step 81: The client sets the storage status of the current electronic fingerprint data to "not yet stored"; and adds a corresponding first cache data, composed of the current electronic fingerprint data and the corresponding operation type, to a preset first cache queue; and takes the first network node on the storage blockchain that is closest to the current user as the corresponding current storage node.

[0037] When the first cache queue is not empty, it consists of one or more of the first cached data.

[0038] Step 82: When the first cache queue is not empty, the earliest first cache data in the queue is taken as the corresponding current cache data; and based on the ledger block data encapsulation rules of the feature-based evidence ledger, the current cache data is encapsulated to obtain the corresponding current new block; and the current new block is updated on the entire chain ledger through the current evidence node; and after the entire chain ledger update is successful, the current cache data is deleted from the first cache queue, and the evidence storage status of the electronic fingerprint data corresponding to the current cache data is set to evidence storage successful.

[0039] Preferably, the step of performing medical data operations based on the user monitoring data after successful evidence storage and feeding back the operation results to the current user specifically includes:

[0040] Step 91: When the storage status corresponding to the electronic fingerprint data is set to successful storage, the client takes the user monitoring data corresponding to the current electronic fingerprint data as the corresponding current monitoring data; and extracts the corresponding object identifier, operation type and operation data from the current monitoring data.

[0041] Step 92, and identify the operation type;

[0042] Step 93: If the operation type is add or modify, the operation data is treated as a corresponding current medical data object, and the current medical data object is uploaded to the storage location corresponding to the object identifier in the medical data sharing network. When the upload ends, feedback is sent to the current user that the operation has been completed.

[0043] Step 94: If the operation type is deletion, delete the medical data object stored in the storage location corresponding to the object identifier in the medical data sharing network, and provide feedback to the current user that the operation has been completed when the deletion is finished;

[0044] Step 95: If the operation type is download, the medical data object stored in the storage location corresponding to the object identifier in the medical data sharing network is downloaded to the storage location specified by the current user, and feedback is sent to the current user that the operation has been completed when the download ends.

[0045] A second aspect of the present invention provides an apparatus for implementing the blockchain evidence storage method for medical data operation features as described in the first aspect above. The apparatus includes: a behavior monitoring module, an operation feature extraction module, a zero-knowledge proof verification module, and a blockchain evidence storage module.

[0046] The behavior monitoring module is used to monitor the medical data operations performed by users on the portal webpage provided by the medical data sharing network in real time to obtain corresponding user monitoring data. The user monitoring data includes an object identifier, an operation type, and operation data. The object identifier is the routing identifier path of the medical data object currently operated by the user. The routing identifier path consists of a routing identifier prefix and an end routing identifier, and the routing identifier path corresponds to a specific data storage location on the medical data sharing network. The operation type includes at least add, modify, delete, and download. When the operation type is add or modify, the operation data is one medical data object. When the operation type is delete or download, the operation data is empty.

[0047] The operation feature extraction module is used to extract operation features based on the current user's private information and the user monitoring data to obtain corresponding operation feature data; and to obtain the blockchain timestamp from the evidence storage blockchain as the corresponding operation time; and to form corresponding private data from the operation feature data and the operation time; the operation feature data includes the user's private key, the object identifier, and the operation type;

[0048] The zero-knowledge proof verification module is used to generate a zero-knowledge proof π based on the private data using zero-knowledge proof technology, and send it to the evidence storage blockchain for verification to obtain the corresponding verification result.

[0049] The blockchain evidence storage module is used to generate electronic fingerprint data based on the private data when the verification result is successful; and to perform on-chain evidence storage on the electronic fingerprint data through asynchronous processing of the cache queue; and to perform medical data operations based on the user monitoring data after successful evidence storage and to provide feedback on the operation results to the current user.

[0050] A third aspect of the present invention provides an electronic device, including: a memory, a processor, and a transceiver;

[0051] The processor is used to couple with the memory, read and execute instructions in the memory to implement the steps of the method described in the first aspect above;

[0052] The transceiver is coupled to the processor, and the processor controls the transceiver to send and receive messages.

[0053] A fourth aspect of the present invention provides a computer-readable storage medium storing computer instructions that, when executed by a computer, cause the computer to perform the instructions described in the first aspect.

[0054] This invention provides a blockchain-based method, apparatus, electronic device, and computer-readable storage medium for storing medical data operation features. As described above, this invention monitors user actions on a portal webpage provided by a medical data sharing network in real time to obtain corresponding user monitoring data. It extracts operation features based on the user's private information and the user monitoring data to obtain corresponding operation feature data. A blockchain timestamp is obtained from the storage blockchain as the corresponding operation time. The operation feature data and operation time form corresponding private data. A zero-knowledge proof π is generated based on the private data using zero-knowledge proof technology and sent to the storage blockchain for verification to obtain the corresponding verification result. If the verification result is successful, an electronic fingerprint is generated based on the private data to obtain corresponding electronic fingerprint data. The electronic fingerprint data is then stored on the blockchain using an asynchronous processing method with a cache queue. After successful storage, medical data operations are performed based on the user monitoring data, and the operation results are fed back to the current user. This invention uses a storage blockchain with a distributed ledger service to record user data access / operation behavior, improving both data tamper-proof capabilities and proactive data backup capabilities. Attached Figure Description

[0055] Figure 1 A schematic diagram of a blockchain-based evidence storage method for medical data operation features provided in Embodiment 1 of the present invention;

[0056] Figure 2 This is a module structure diagram of a blockchain evidence storage device for medical data operation features provided in Embodiment 2 of the present invention;

[0057] Figure 3 This is a schematic diagram of the structure of an electronic device provided in Embodiment 3 of the present invention. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0059] Embodiment 1 of the present invention provides a blockchain-based evidence storage method for medical data operation features, such as... Figure 1 The schematic diagram of a blockchain-based evidence storage method for medical data operation features provided in Embodiment 1 of the present invention is shown. The method mainly includes the following steps:

[0060] Step 1: The client monitors the medical data operations performed by the user on the portal webpage provided by the medical data sharing network in real time to obtain the corresponding user monitoring data.

[0061] Here, the client in this embodiment of the invention is a module, application software, device, equipment, server, or system that accesses a medical data sharing network.

[0062] The medical data sharing network of this invention is a distributed data sharing network composed of multiple first network nodes. Each first network node in the network corresponds to a node type, which includes at least a portal website node, a data storage node, and a data computing node. Specifically: 1) First network nodes of the portal website node type provide access services to the portal webpage; 2) First network nodes of the data storage node type store medical data objects; 3) First network nodes of the data computing node type provide data storage services, data encryption / decryption services, and algorithm / model inference services.

[0063] The evidence-keeping blockchain mentioned below is built based on data computing nodes in a medical data sharing network. Specifically, the construction method is as follows: when building the evidence-keeping blockchain, the first network node of each node type in the medical data sharing network that is a data computing node is designated as the corresponding first candidate node; the importance parameter W of each first candidate node is initialized based on security indicator A, reachability indicator B, throughput indicator C, and real-time indicator D; and the PageRank algorithm is used to iterate through all importance parameters W multiple times until the absolute difference between the two most recent iterations of all importance parameters W does not exceed a preset first threshold. So far; and sort the first candidate nodes in descending order of importance parameter W to form the corresponding first node sequence; and form the corresponding evidence storage blockchain from the top K first candidate nodes in the first node sequence; and deploy distributed ledger business on the evidence storage blockchain based on blockchain technology; wherein, security indicator A, reachability indicator B, throughput indicator C and real-time indicator D are each a normalized numerical indicator; the initial importance parameter W = w1A + w2B + w3C + w4D, where w1, w2, w3, and w4 are four preset weight parameters; the first threshold is a pre-set threshold parameter.

[0064] In other words, the node network of the evidence-preserving blockchain in this embodiment of the invention is a distributed node network composed of multiple first network nodes of the data computing node type in the medical data sharing network; a distributed ledger service is deployed on this distributed node network based on blockchain technology. Based on the characteristics of the distributed ledger service, we know that: all first network nodes of the blockchain network in this embodiment of the invention jointly maintain a feature-based evidence-preserving ledger based on blockchain technology, and all first network nodes have a complete copy of the ledger; all first network nodes on the evidence-preserving blockchain maintain full-chain time synchronization through an external time synchronization server.

[0065] The user monitoring data in this embodiment of the invention includes an object identifier, an operation type, and operation data. The object identifier is the routing path of the medical data object currently being operated on by the user. The routing path consists of a routing identifier prefix and an end routing identifier, and corresponds to a specific data storage location on the medical data sharing network. The operation type includes at least add, modify, delete, and download. When the operation type is add or modify, the operation data is a medical data object; when the operation type is delete or download, the operation data is empty.

[0066] Step 2: The client extracts operation features based on the current user's private information and user monitoring data to obtain the corresponding operation feature data; it also obtains the blockchain timestamp from the evidence storage blockchain as the corresponding operation time; and the operation feature data and operation time are combined to form the corresponding private data.

[0067] Specifically, this includes: Step 21, extracting operation features based on the current user's private information and user monitoring data to obtain corresponding operation feature data;

[0068] The operation feature data includes the user's private key, object identifier, and operation type;

[0069] Specifically, this includes: corresponding operation feature data composed of the current user's private key, the object identifier of the user monitoring data, and the operation type;

[0070] Step 22, and obtain the blockchain timestamp from the evidence storage blockchain as the corresponding operation time;

[0071] Specifically, this includes: designating the first network node on the blockchain closest to the current user as the corresponding current time synchronization node; sending the first time synchronization request to the current time synchronization node; and using the first timestamp returned by the current time synchronization node as the corresponding operation time.

[0072] Step 23, and the corresponding private data is composed of operation feature data and operation time;

[0073] Here, the private data in this embodiment of the invention includes the user's private key, object identifier, operation type, and operation time.

[0074] Step 3: The client generates a zero-knowledge proof π based on the private data using zero-knowledge proof technology and sends it to the evidence storage blockchain for verification to obtain the corresponding verification result;

[0075] Specifically, this includes: Step 31, where the client generates a shared first CRS for the current user and the evidence storage blockchain according to the Common Reference String (CRS) generation method of zk-SNARKs zero-knowledge proof technology;

[0076] Step 32: According to the arithmetic circuit configuration method of zk-SNARKs zero-knowledge proof technology, generate a shared first arithmetic circuit for the current user and the evidence storage blockchain based on the preset permission verification rules;

[0077] Here, the permission verification rules in this embodiment of the invention include operation type verification rules and operation time verification rules; wherein, the operation type verification rule consists of multiple object-permission correspondences; each object-permission correspondence consists of a route identifier prefix and a type of operation permission; the types of operation permissions include add permission, modify permission, delete permission, and download permission; the permission values ​​of each type of operation permission include allow and prohibit; the operation time verification rule is that the time interval between the current time and the operation time cannot exceed a preset time interval threshold;

[0078] The inputs of the first arithmetic circuit in this embodiment of the invention are the object identifier prefix d, the object operation type s, the object operation time t, and the current time t. now The output is the verification result r; the verification result r is 0 or 1, where 0 indicates verification failure and 1 indicates verification success.

[0079] The processing logic of the first arithmetic circuit in this embodiment of the invention is as follows: if the object identifier prefix d and the object operation type s satisfy one type of object-permission correspondence in the operation type verification rules, then the first result is set to 1; if the object identifier prefix d and the object operation type s do not satisfy any type of object-permission correspondence in the operation type verification rules, then the first result is set to 0; if the current time t now If the absolute time difference between the current time t and the object operation time t does not exceed the time interval threshold, then the second result is set to 1; if the current time t... now If the absolute time difference between the first and second results exceeds the time interval threshold, the second result is set to 0; and the product of the first and second results is used as the corresponding verification result r.

[0080] Step 33: Extract the corresponding user private key, object identifier, operation type, and operation time from the private data;

[0081] Step 34: Use the route identifier prefix of the object identifier as the corresponding object identifier prefix d; use the operation type as the corresponding object operation type s; use the operation time as the corresponding object operation time t; and use the current time information as the corresponding current time t. now The obtained object identifier prefix d, object operation type s, object operation time t, and current time t will be processed. now The input is processed by the first arithmetic circuit to obtain the corresponding verification result r;

[0082] Step 35: If the verification result r obtained this time is 1, then the process data of the first arithmetic circuit in this processing is extracted to form the corresponding first evidence according to the zero-knowledge evidence acquisition method of zk-SNARKs zero-knowledge proof technology; and the first evidence is hashed according to the zero-knowledge commitment generation method of zk-SNARKs zero-knowledge proof technology, and the calculation result is used as the corresponding first commitment; and the first evidence is signed based on the user's private key to obtain the corresponding first signature; and the user's public key corresponding to the user's private key is used as the corresponding first public key; and the corresponding zero-knowledge proof π composed of the first public key, the first commitment, the first evidence and the first signature is sent to the evidence storage blockchain; and the zero-knowledge proof verification result sent back by the evidence storage blockchain is used as the corresponding verification result.

[0083] Here, the verification process of the evidence-based blockchain in this embodiment of the invention after receiving the zero-knowledge proof π is as follows:

[0084] Step A1: Extract the corresponding first public key, first commitment, first evidence, and first signature from the zero-knowledge proof π;

[0085] Step A2, and verify the first signature based on the first public key and the first evidence; and set the first comparison result to match if the verification is successful, and set the first comparison result to mismatch if the verification fails.

[0086] Step A3: Perform hash calculation on the first evidence according to the zero-knowledge commitment generation method of zk-SNARKs zero-knowledge proof technology and use the calculation result as the corresponding second commitment; identify whether the first and second commitments match. If they match, set the second comparison result as a match; if they do not match, set the second comparison result as a mismatch.

[0087] Step A4, and load the first evidence as process data onto the shared first arithmetic circuit for further processing to obtain a new verification result r; and identify whether the verification result r obtained this time is 1. If it is, set the third comparison result as a match; otherwise, set the third comparison result as a mismatch.

[0088] Step A5 involves identifying whether the first, second, and third comparison results are all matches; if yes, the corresponding zero-knowledge proof verification result is set to "verification passed"; if no, the corresponding zero-knowledge proof verification result is set to "verification failed"; and the obtained zero-knowledge proof verification result is sent back to the client.

[0089] Step 4: When the verification result is successful, the client generates the corresponding electronic fingerprint data based on the private data; and performs on-chain storage of the electronic fingerprint data through asynchronous processing of the cache queue; and after successful storage, performs medical data operations based on user monitoring data and feeds back the operation results to the current user.

[0090] Specifically, this includes: Step 41, when the verification result is successful, electronic fingerprint generation processing is performed based on the private data to obtain the corresponding electronic fingerprint data;

[0091] Specifically, this includes: extracting the corresponding user private key and object identifier from private data; performing digest calculations on the user private key and object identifier based on the national cryptographic SM3 algorithm to obtain the corresponding private key digest and identifier digest; sequentially concatenating the private key and identifier digests to form the corresponding concatenated digest; performing two digest calculations on the concatenated digest based on the national cryptographic SM3 algorithm to obtain the corresponding first and second digests; and sequentially concatenating the first and second digests to form the corresponding electronic fingerprint data.

[0092] Among them, the private key digest, the identifier digest, the first digest, and the second digest are all 128-bit digital digests; the concatenated digest and the electronic fingerprint data are all 256-bit digital digests.

[0093] Step 42, and perform on-chain evidence storage processing on the electronic fingerprint data through the asynchronous processing method of the cache queue;

[0094] Specifically, this includes: step 421, setting the current electronic fingerprint data to a storage status of not yet stored; adding a corresponding first cache data composed of the current electronic fingerprint data and the corresponding operation type to a preset first cache queue; and taking the first network node on the storage blockchain that is closest to the current user as the corresponding current storage node;

[0095] When the first cache queue is not empty, it consists of one or more first cache data.

[0096] Step 422: When the first cache queue is not empty, the earliest cached data in the queue is taken as the corresponding current cached data; and based on the ledger block data encapsulation rules of the feature-based evidence ledger, the current cached data is encapsulated to obtain the corresponding newly added block; and the current newly added block is updated across the entire chain ledger through the current evidence node; and after the full chain ledger update is successful, the current cached data is deleted from the first cache queue, and the evidence storage status of the electronic fingerprint data corresponding to the current cached data is set to successful evidence storage.

[0097] Step 43, and after successful evidence storage, perform medical data operations based on user monitoring data and provide feedback on the operation results to the current user;

[0098] Specifically, this includes: Step 431, when the storage status corresponding to the electronic fingerprint data is set to successful storage, the user monitoring data corresponding to the current electronic fingerprint data is used as the corresponding current monitoring data; and the corresponding object identifier, operation type and operation data are extracted from the current monitoring data;

[0099] Step 432, and identify the operation type;

[0100] Step 433: If the operation type is add or modify, the operation data is treated as a corresponding current medical data object, and the current medical data object is uploaded to the storage location corresponding to the object identifier in the medical data sharing network. When the upload is finished, feedback is sent to the current user that the operation has been completed.

[0101] Step 434: If the operation type is deletion, delete the medical data object stored in the storage location corresponding to the object identifier in the medical data sharing network, and provide feedback to the current user that the operation has been completed when the deletion is finished.

[0102] Step 435: If the operation type is download, the medical data object stored at the storage location corresponding to the object identifier in the medical data sharing network is downloaded to the storage location specified by the current user, and feedback is sent to the current user that the operation has been completed when the download is finished.

[0103] Figure 2 This is a module structure diagram of a blockchain-based evidence storage device for medical data operation features provided in Embodiment 2 of the present invention. This device can be a terminal device or server implementing the aforementioned method embodiments, or it can be a device that enables the aforementioned terminal device or server to implement the aforementioned method embodiments. For example, the device can be a device or chip system of the aforementioned terminal device or server. Figure 2 As shown, the device includes: a behavior monitoring module 201, an operation feature extraction module 202, a zero-knowledge proof verification module 203, and a blockchain evidence storage module 204.

[0104] The behavior monitoring module 201 is used to monitor the medical data operations performed by users on the portal webpage provided by the medical data sharing network in real time and obtain the corresponding user monitoring data. The user monitoring data includes object identifier, operation type and operation data. The object identifier is the routing identifier path of the medical data object currently operated by the user. The routing identifier path consists of a routing identifier prefix and an end routing identifier. The routing identifier path corresponds to a specific data storage location on the medical data sharing network. The operation type includes at least add, modify, delete and download. When the operation type is add or modify, the operation data is a medical data object. When the operation type is delete or download, the operation data is empty.

[0105] The operation feature extraction module 202 is used to extract operation features based on the current user's private information and user monitoring data to obtain corresponding operation feature data; and to obtain the blockchain timestamp from the evidence storage blockchain as the corresponding operation time; and to form corresponding private data from the operation feature data and the operation time; the operation feature data includes the user's private key, object identifier, and operation type.

[0106] The zero-knowledge proof verification module 203 is used to generate a zero-knowledge proof π based on private data using zero-knowledge proof technology, and send it to the evidence storage blockchain for verification to obtain the corresponding verification result.

[0107] The blockchain evidence storage module 204 is used to generate electronic fingerprint data based on private data when the verification result is successful; and to perform on-chain evidence storage processing on the electronic fingerprint data through the asynchronous processing method of the cache queue; and to perform medical data operation based on user monitoring data after successful evidence storage and to provide feedback on the operation results to the current user.

[0108] The blockchain evidence storage device for medical data operation features provided in this embodiment of the invention can execute the method steps in the above method embodiment. Its implementation principle and technical effect are similar, and will not be repeated here.

[0109] It should be noted that the division of the various modules in the above device is merely a logical functional division. In actual implementation, they can be fully or partially integrated into a single physical entity, or they can be physically separated. Furthermore, these modules can be implemented entirely in software via processing element calls; they can be fully implemented in hardware; or some modules can be implemented by processing element calls to software, while others are implemented in hardware. For example, the behavior monitoring module can be a separate processing element, or it can be integrated into a chip in the above device. Alternatively, it can be stored as program code in the memory of the above device, and called and executed by a processing element of the device. The implementation of other modules is similar. Moreover, these modules can be fully or partially integrated together, or they can be implemented independently. The processing element described here can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each of the above modules can be completed through integrated logic circuits in the hardware of the processor element or through software instructions.

[0110] For example, these modules can be one or more integrated circuits configured to implement the above methods, such as one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), or one or more Field Programmable Gate Arrays (FPGAs). As another example, when a module is implemented using processing element scheduler code, the processing element can be a general-purpose processor, such as a Central Processing Unit (CPU) or other processor capable of calling program code. Furthermore, these modules can be integrated together as a System-on-a-Chip (SOC).

[0111] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. This computer program product includes one or more computer instructions. When these computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the foregoing method embodiments are generated. The computer described above can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The aforementioned computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the aforementioned computer instructions can be transmitted from one website, computer, server, or data center to another via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, Bluetooth, microwave, etc.) means. The aforementioned computer-readable storage medium can be any available medium that a computer can access, or a data storage device such as a server or data center that integrates one or more available media. The aforementioned available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state disks (SSDs)).

[0112] Figure 3 This is a schematic diagram of an electronic device provided in Embodiment 3 of the present invention. This electronic device can be a terminal device or server implementing the methods of the aforementioned embodiments, or it can be a terminal device or server connected to the aforementioned terminal device or server implementing the methods of the aforementioned embodiments. Figure 3 As shown, the electronic device may include: a processor 301 (e.g., CPU), a memory 302, and a transceiver 303; the transceiver 303 is coupled to the processor 301, and the processor 301 controls the transmission and reception operations of the transceiver 303. The memory 302 may store various instructions for performing various processing functions and implementing the processing steps described in the foregoing embodiments. Preferably, the electronic device involved in the embodiments of the present invention further includes: a power supply 304, a system bus 305, and a communication port 306. The system bus 305 is used to realize communication connections between components. The communication port 306 is used for communication between the electronic device and other peripherals.

[0113] exist Figure 3The system bus 305 mentioned can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This system bus can be divided into address bus, data bus, control bus, etc. For ease of representation, it is represented by only one thick line in the figure, but this does not indicate that there is only one bus or one type of bus. The communication interface is used to enable communication between the database access device and other devices (e.g., clients, read-write libraries, and read-only libraries). Memory may include Random Access Memory (RAM) and may also include non-volatile memory, such as at least one disk storage device.

[0114] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), graphics processing units (GPUs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0115] It should be noted that the embodiments of the present invention also provide a computer-readable storage medium storing instructions that, when run on a computer, cause the computer to perform the methods and processes provided in the above embodiments.

[0116] This invention provides a blockchain-based method, apparatus, electronic device, and computer-readable storage medium for storing medical data operation features. As described above, this invention monitors user actions on a portal webpage provided by a medical data sharing network in real time to obtain corresponding user monitoring data. It extracts operation features based on the user's private information and the user monitoring data to obtain corresponding operation feature data. A blockchain timestamp is obtained from the storage blockchain as the corresponding operation time. The operation feature data and operation time form corresponding private data. A zero-knowledge proof π is generated based on the private data using zero-knowledge proof technology and sent to the storage blockchain for verification to obtain the corresponding verification result. If the verification result is successful, an electronic fingerprint is generated based on the private data to obtain corresponding electronic fingerprint data. The electronic fingerprint data is then stored on the blockchain using an asynchronous processing method with a cache queue. After successful storage, medical data operations are performed based on the user monitoring data, and the operation results are fed back to the current user. This invention uses a storage blockchain with a distributed ledger service to record user data access / operation behavior, improving both data tamper-proof capabilities and proactive data backup capabilities.

[0117] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented in hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0118] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A blockchain storage method of medical data operation features, characterized in that, The method comprises: The client monitors the medical data operation actions performed by the user on the portal webpage provided by the medical data sharing network in real time to obtain corresponding user monitoring data; the user monitoring data includes object identification, operation type and operation data; the object identification is the routing identification path of the medical data object currently operated by the user, the routing identification path consists of a routing identification prefix and a terminal routing identification, the routing identification path corresponds to a specific data storage location on the medical data sharing network; the operation type at least includes addition, modification, deletion and download; when the operation type is addition or modification, the operation data is a medical data object; when the operation type is deletion or download, the operation data is empty; According to the current user's private information and the user monitoring data, operation feature extraction is performed to obtain corresponding operation feature data; and a blockchain timestamp is obtained from a storage blockchain to serve as a corresponding operation time; and the operation feature data and the operation time are combined to form corresponding private data; the operation feature data includes a user private key, the object identification and the operation type; According to the zero-knowledge proof technology, a zero-knowledge proof π is generated according to the private data and sent to the storage blockchain for verification to obtain a corresponding verification result; When the verification result is verified, electronic fingerprint generation processing is performed according to the private data to obtain corresponding electronic fingerprint data; and the electronic fingerprint data is stored in the chain through the asynchronous processing mode of the cache queue; and after the storage is successful, medical data operation is performed based on the user monitoring data and the operation result is fed back to the current user; The medical data sharing network is a distributed data sharing network composed of a plurality of first network nodes; each first network node corresponds to a node type, and the node type at least includes a portal website node, a data storage node and a data calculation node; The node network of the storage blockchain is a distributed node network composed of a plurality of first network nodes of the node type of data calculation node in the medical data sharing network, and a distributed ledger business is deployed on the distributed node network based on blockchain technology; When the storage blockchain is constructed, each first network node of the node type of data calculation node in the medical data sharing network is recorded as a corresponding first candidate node; and the importance parameter W of each first candidate node is initialized and set based on a security index A, an accessibility index B, a throughput rate index C and a real-time index D; and the PageRank algorithm is used to iterate all the importance parameters W for multiple times until the absolute difference between the latest two iteration results of all the importance parameters W does not exceed a preset first threshold value; and the first candidate nodes are sorted in descending order of the importance parameters W to form a corresponding first node sequence; and the storage blockchain is formed by the K first candidate nodes with high ranking in the first node sequence. The zero-knowledge proof technology generates a zero-knowledge proof π from the private data and sends it to the storage evidence blockchain for verification to obtain a corresponding verification result, specifically including: Step 51, the client generates a shared first CRS for the current user and the storage evidence blockchain according to the public reference string (CRS) generation mode of the zk-SNARKs zero-knowledge proof technology; Step 52, according to the arithmetic circuit configuration mode of the zk-SNARKs zero-knowledge proof technology, a shared first arithmetic circuit is generated for the current user and the storage evidence blockchain according to the preset permission verification rule; The input of the first arithmetic circuit is object identification prefix d, object operation type s, object operation time t, and current time t now , and the output is verification result r; the verification result r is 0 or 1, 0 indicating verification failure and 1 indicating verification success; Step 53, the corresponding user private key, object identifier, operation type, and operation time are extracted from the private data; Step 54, taking the route identification prefix of the object identification as the corresponding object identification prefix d; and taking the operation type as the corresponding object operation type s; and taking the operation time as the corresponding object operation time t; and taking the current time information as the corresponding current time t now ; and taking the obtained object identification prefix d, object operation type s, object operation time t, and current time t now Inputting the first arithmetic circuit for processing to obtain the corresponding verification result r; Step 55, if the verification result r obtained this time is 1, the process data in the first arithmetic circuit this time is extracted to form a corresponding first evidence according to the zero-knowledge evidence acquisition mode of the zk-SNARKs zero-knowledge proof technology; and the first evidence is subjected to hash calculation according to the zero-knowledge commitment generation mode of the zk-SNARKs zero-knowledge proof technology, and the calculation result is taken as a corresponding first commitment; and the first evidence is signed based on the user private key to obtain a corresponding first signature; and the user public key corresponding to the user private key is taken as a corresponding first public key; and the first public key, the first commitment, the first evidence, and the first signature are combined to form a corresponding zero-knowledge proof π which is sent to the storage evidence blockchain; and the zero-knowledge proof verification result returned by the storage evidence blockchain is taken as a corresponding verification result; The storage evidence blockchain extracts the first public key, the first commitment, the first evidence, and the first signature from the zero-knowledge proof π; And the first signature is subjected to signature verification processing according to the first public key and the first evidence; and when the current signature verification passes, the first comparison result is set to match, and when the current signature verification fails, the first comparison result is set to not match; And the first evidence is subjected to hash calculation according to the zero-knowledge commitment generation mode of the zk-SNARKs zero-knowledge proof technology, and the calculation result is taken as a corresponding second commitment; and whether the first and second commitments match is identified, if they match, the second comparison result is set to match, if they do not match, the second comparison result is set to not match; And the first evidence is loaded as process data onto the shared first arithmetic circuit for further processing to obtain a new verification result r; and whether the verification result r obtained this time is 1 is identified, if it is, the third comparison result is set to match, if it is not, the third comparison result is set to not match; And whether the first, second, and third comparison results obtained are all match is identified; if so, the corresponding zero-knowledge proof verification result is set to pass verification; if not, the corresponding zero-knowledge proof verification result is set to fail verification; and the zero-knowledge proof verification result obtained is returned to the client. 2.The medical data operation feature blockchain notarization method according to claim 1, characterized in that, The method further includes: The first network node of the node type of a portal website node is configured to provide access to a portal webpage; the first network node of the node type of a data storage node is configured to store the medical data object; the first network node of the node type of a data computing node is configured to provide data storage services, data encryption and decryption services, and algorithm / model inference services; All the first network nodes of the blockchain network jointly maintain a feature storage ledger based on blockchain technology, and all the first network nodes have complete copies of the ledger; all the first network nodes on the storage blockchain keep the time synchronization of the entire chain through an external time server; The security indicator A, the accessibility indicator B, the throughput rate indicator C, and the real-time indicator D are each a normalized numerical indicator; the initialized importance parameter W = w1A + w2B + w3C + w4D, w1, w2, w3, and w4 are four preset weight parameters. 3.The medical data operation feature blockchain notarization method according to claim 1, characterized in that, The operation feature data corresponding to the current user's private information and the user monitoring data is obtained by operation feature extraction, specifically including: The client consists of the user private key of the current user, the object identifier of the user monitoring data, and the operation type to form the corresponding operation feature data. 4.The medical data operation feature blockchain notarization method according to claim 1, characterized in that, The blockchain timestamp on the storage blockchain is obtained as the corresponding operation time, specifically including: The client takes the first network node closest to the current user on the storage blockchain as the corresponding current time server, sends a first time request to the current time server, and takes the first timestamp returned by the current time server as the corresponding operation time.

5. The medical data operation feature blockchain storage method of claim 1, characterized in that, The permission verification rule includes an operation type verification rule and an operation time verification rule; the operation type verification rule consists of a plurality of object-permission corresponding relationships; the object-permission corresponding relationship consists of a routing identifier prefix and a type of operation permission; the type of operation permission includes add permission, modify permission, delete permission, and download permission; The permission value of each type of operation permission includes allow and prohibit; the operation time verification rule is that the time interval between the current time and the operation time cannot exceed a preset time interval threshold; The processing logic of the first arithmetic circuit is: if the object identification prefix d and the object operation type s satisfy one of the object-right corresponding relations in the operation type verification rule, set the first result as 1, if the object identification prefix d and the object operation type s do not satisfy any of the object-right corresponding relations in the operation type verification rule, set the first result as 0; if the current time t now And the absolute time difference of the object operation time t does not exceed the time interval threshold, set the second result as 1, if the current time t now And the absolute time difference of the object operation time t exceeds the time interval threshold, set the second result as 0; and the product of the first and second results is used as the corresponding verification result r. 6.The medical data operation feature blockchain notarization method according to claim 1, characterized in that, The electronic fingerprint data corresponding to the private data is obtained by electronic fingerprint generation processing, specifically including: The client extracts the user private key and the object identifier from the private data; and based on the SM3 algorithm, the user private key and the object identifier are respectively calculated to obtain the private key digest and the identifier digest; and the private key digest and the identifier digest are sequentially spliced to form a spliced digest; and based on the SM3 algorithm, the spliced digest is calculated twice to obtain the first and second digests; and the first and second digests are sequentially spliced to form the electronic fingerprint data. The private key digest, the identity digest, the first digest, and the second digest are all 128-bit digital digests; and the spliced digest and the electronic fingerprint data are both 256-bit digital digests. 7.The medical data operation feature blockchain notarization method according to claim 2, characterized in that, The asynchronous processing mode through the cache queue is used to perform the on-chain storage evidence processing on the electronic fingerprint data, and specifically includes the following steps: In step 81, the client sets the storage evidence state corresponding to the current electronic fingerprint data as not yet stored, and adds a corresponding first cache data composed of the current electronic fingerprint data and the corresponding operation type to a preset first cache queue; and sets the first network node closest to the current user on the storage evidence block chain as a corresponding current storage evidence node. The first cache queue is composed of one or more first cache data when the first cache queue is not empty. In step 82, when the first cache queue is not empty, the first cache data with the earliest time in the queue is taken as a corresponding current cache data; and a current new block is obtained by performing block encapsulation processing on the current cache data based on the account block data encapsulation rule of the feature storage account book; and the current new block is updated on the full-chain account book through the current storage evidence node; and after the full-chain account book update processing is successful, the current cache data is deleted from the first cache queue, and the storage evidence state of the electronic fingerprint data corresponding to the current cache data is set as storage evidence success. 8.The medical data operation feature blockchain notarization method according to claim 1, characterized in that, After the storage evidence is successful, the medical data operation is performed based on the user monitoring data, and the operation result is fed back to the current user, and specifically includes the following steps: In step 91, when the storage evidence state corresponding to the electronic fingerprint data is set as storage evidence success, the client takes the user monitoring data corresponding to the current electronic fingerprint data as a corresponding current monitoring data; and extracts the object identifier, the operation type, and the operation data corresponding to the current monitoring data. In step 92, the operation type is identified. In step 93, if the operation type is addition or modification, the operation data is taken as a corresponding current medical data object, the current medical data object is uploaded to the storage location corresponding to the object identifier in the medical data sharing network, and the operation is fed back to the current user when the uploading is completed. In step 94, if the operation type is deletion, the medical data object stored in the storage location corresponding to the object identifier in the medical data sharing network is deleted, and the operation is fed back to the current user when the deletion is completed. In step 95, if the operation type is download, the medical data object stored in the storage location corresponding to the object identifier in the medical data sharing network is downloaded to the storage location specified by the current user, and the operation is fed back to the current user when the downloading is completed. 9.A device for performing the blockchain attestation method of the medical data operation feature according to any one of claims 1-8, characterized in that, The device includes a behavior monitoring module, an operation feature extraction module, a zero-knowledge proof verification module, and a block chain storage evidence module. The behavior monitoring module is used for monitoring the medical data operation actions performed by the user on the portal webpage provided by the medical data sharing network in real time to obtain corresponding user monitoring data; the user monitoring data includes object identification, operation type and operation data; the object identification is a routing identification path of the medical data object currently operated by the user, the routing identification path is composed of a routing identification prefix and a terminal routing identification, the routing identification path corresponds to a specific data storage location on the medical data sharing network; the operation type at least includes addition, modification, deletion and download; when the operation type is addition or modification, the operation data is a medical data object; when the operation type is deletion or download, the operation data is empty; The operation feature extraction module is used for extracting operation features according to the private information of the current user and the user monitoring data to obtain corresponding operation feature data; and obtaining a blockchain timestamp from a storage blockchain as a corresponding operation time; and the operation feature data and the operation time form corresponding private data; the operation feature data includes a user private key, the object identification and the operation type; The zero-knowledge proof verification module is used for generating a zero-knowledge proof π according to the private data by zero-knowledge proof technology, and sending the zero-knowledge proof π to the storage blockchain for verification to obtain a corresponding verification result; The blockchain storage module is used for, when the verification result is verified, generating electronic fingerprint data according to the private data; and performing on-chain storage processing on the electronic fingerprint data through the asynchronous processing mode of the cache queue; and performing medical data operation based on the user monitoring data after the storage is successful, and feeding back the operation result to the current user.

10. An electronic device, comprising: Comprise: Memory, processor and transceiver; The processor is used for coupling with the memory, reading and executing the instructions in the memory, so as to realize the method of any one of claims 1-8; The transceiver is coupled with the processor, and the transceiver is controlled by the processor to perform message transmission and reception.

11. A computer readable storage medium, characterized in that, The computer readable storage medium stores computer instructions, when the computer instructions are executed by the computer, the computer executes the method of any one of claims 1-8.

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