Abstract: A method for dynamically evaluating a resource value is described. Data encoding one or more parameters related to the resource value is accessed, where the one or more parameters are monitored by a plurality of sensors that form an Internet of Things (IoT) and then released by the IoT of the plurality of sensors on a blockchain network. At least one parameter from the data is compared with a predetermined threshold value or a predetermined threshold range. In response to determining that the at least one parameter has exceeded the predetermined threshold value or the predetermined threshold range, a calculation of the resource value is triggered according to evaluation logic described by a smart contract released on the blockchain network in association with the one or more parameters being monitored, such that a consensus is reached on the blockchain network regarding the resource value that has been calculated.

Abstract: Embodiments of the present application relate to a method, apparatus, and system for verifying an identity of a user. The method includes receiving a preset key that is associated with a key carrier that is a physical object, storing the preset key in a database storing mappings between a plurality of preset keys and a plurality of users, receiving a verification key in connection with an identity verification of a user, retrieving the preset key associated with the user from the database, determining whether the verification key matches the preset key associated with the user, and causing a determination of whether the key carrier is authentic.

Abstract: Multiple geographic grids are generated according to acquired location information of a service provider. Each geographic grid contains one or more service providers. The second region matching the target location information is a geographic grid for a region defined by the target location information. A presentation request for a search page is received. The presentation request includes target location information. A keyword is acquired that has a search popularity meeting a first condition in a first region matching the target location information, and the acquired keyword is used as a first keyword. The first keyword is provided for presentation in the search page.

Abstract: Implementations of the present disclosure include determining a first number of an index corresponding to one of a first one or more key-value pairs (KVPs) of a Merkle Patricia Tree (MPT) used by a smart contract database; determining, based on the first number of the index, a first key of a first KVP of a second one or more KVPs of a map for traversing the MPT; determining a first value corresponding to the first key of the first KVP; determining a second key of a second KVP of the second one or more KVPs; and retrieving the second value corresponding to the second key of the second KVP.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for retrieving data from external data sources for processing within a blockchain network. One of the methods includes receiving a request for data that includes encrypted data, the encrypted data including access data that is encrypted using a service public key of a key management node; selecting a relay system node from a plurality of relay system nodes that share a service private key of the key management node; transmitting the request to the relay system node; receiving a response provided from the relay system node, the response including result data and a digital signature, wherein the digital signature is generated based on the result data and the service private key of the key management node; and transmitting the response to a client.

Abstract: Implementations of the present specification disclose mobile payment methods, apparatuses, and devices. In one aspect, the method includes: monitoring, by a terminal device that is in lock screen mode, outputs of one or more sensors of the terminal device; determining that the outputs of the one or more sensors satisfy first specified criteria indicative of one or more particular body movements; in response to determining that the outputs of the one or more sensors satisfy the first specified criteria, displaying, on the terminal device, a payment processing interface; receiving an input through the payment processing interface; and executing a payment service based on the input.

Abstract: Blockchain-based exchange method and apparatus for available resource quotas are disclosed. An example of method comprises: selecting, by a management node of a blockchain network, a set of object nodes as a target object according to a selection rule; determining, by the management node for each object node in the target object, a resource quota; determining, by the management node for the each object node, virtual resources corresponding to the resource quota as virtual resource decrements corresponding to the object node; and constructing, by the management node, a quota exchange transaction comprising the determined virtual resource decrements corresponding to the object node, and adding the quota exchange transaction to a blockchain on the blockchain network.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for communicating and sharing blockchain data. One of the methods includes sending current state information associated with a current block of a blockchain to one or more shared storage nodes of the blockchain network; sending a hash value to the one of the one or more shared storage nodes for retrieving an account state stored in the historic state tree; receiving the account state in response to sending the hash value; and verifying, by the consensus node, that the account state is part of the blockchain based on the hash value.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for authenticating a user based on passive affective and knowledge-based authentication (AKBA). In one aspect, a method includes data associated with eye movements and ocular dynamics of the user are captured with a camera as the user looks at a graphical user interface (GUI) of a device; an AKBA signature of the user is determined based on the captured data; the user is authenticated based on a comparison of the AKBA signature with an AKBA template associated with the user; and an access to a subset of functions of an application is granted.

Abstract: A computer-implemented method for processing blockchain-based transactions, the computer-implemented method including: receiving a target transaction initiated by a member node device in a blockchain, wherein the target transaction comprises a unique identifier of the target transaction; querying a transaction idempotent table on the block chain to determine whether the transaction idempotent table has stored a transaction idempotent record corresponding to the unique identifier of the target transaction; and in response to determining that the transaction idempotent table has not stored the transaction idempotent record corresponding to the unique identifier of the target transaction, recording the target transaction in a candidate block on the blockchain.

Abstract: One or more implementations of the present specification provide a blockchain-based data authorization method and apparatus. The method can include receiving, by a blockchain node, an authentication transaction submitted by a privacy computing platform, where the authentication transaction queries whether a data user has obtained authorization of target data possessed by a data owner, and in response to determining that the data user has obtained authorization of the target data, executing, by the blockchain node, a smart contract invoked by the authentication transaction to provide an authorization token to the privacy computing platform that instructs the privacy computing platform to obtain the target data, and send a computational result of one or more predetermined computational operations based on the target data to the data user.

Abstract: An authorizing party determines an authorization record set that needs to be revoked, where an authorization record included in the authorization record set corresponds to a token that is issued to an authorized party after the authorizing party grants access to the authorized party, and where each authorization record includes an authorization validation moment for a corresponding token. A time validity attribute of the authorization record set is configured. For a specific point-in-time, a value associated with the time validity attribute is set. A determination is performed as to whether the authorization record is revoked based on the authorization validation moment and the value associated with the time validity attribute.

Abstract: Implementations of the present disclosure include setting, by a first consensus node, a timer that runs out before a timeout of a view change; sending, to a second consensus node, a request for one or more consensus messages missing by the first consensus node in response to the timer running out; receiving, from the second consensus node, the one or more consensus messages each digitally signed by a private key of a corresponding consensus node that generates the respective one or more consensus messages; and determining that a block of transactions is valid, if a quantity of commit messages included in the received one or more consensus messages is greater than or equal to 2f+1, where f is a maximum number of faulty nodes that is tolerable by the blockchain based on practical Byzantine fault tolerance.

Abstract: A service request is received by a terminal device. First biometric authentication information of a user associated with the service request is collected. The first biometric authentication information is compated with preset biometric authentication information. When the comparison shows that the first biometric authentication information and the preset biometric authentication information are consistent, a pre-stored digital signature certificate private key is read. The service request is digitally signed according to the digital signature certificate private key. A biometric information verification message is generated and sent message to a server. The server is configured to read a pre-stored digital signature certificate public key corresponding to the digital signature certificate private key. Authentication result information is receiving from the server after the server verifies and signs the biometric information verification message according to the digital signature certificate public key.

Abstract: A computer-implemented certificate verification method includes: obtaining, by a certificate verification module, at least two images of a certificate, in which the at least two images are acquired under different acquisition conditions; obtaining, from the at least two images, at least two target images that correspond to respective images of the at least two images and that each include an image of a light-reflective coating of the certificate; and determining, based on the at least two target images, a probability that the certificate is an original.

Abstract: The technology described in this document can be embodied in a method that includes receiving, at one or more servers from a first computing device, (i) authentication information identifying a user-account associated with (a) the first computing device or (b) an application executing on the first computing device, and (ii) a transaction identifier generated by a second computing device. The transaction identifier is obtained by the first computing device by detecting one or more parameters of a magnetic field generated by the second computing device. The method also includes determining, by the one or more servers, that the user-account is authorized to initiate a transaction identified by the transaction identifier, and in response to determining that the user-account is authorized to initiate the transaction, transmitting, from the one or more servers to the second computing device, confirmation information usable by the second computing device to proceed with the transaction.

Abstract: Behavior data associated with a user is obtained. The behavior data is generated when the user uses an Internet service and includes a user identification and identification information indicating the Internet service. At least one predefined carbon-saving quantity quantization algorithm is determined based on the identification information related to the Internet service. A carbon-saving quantity associated with the user is calculated based on the obtained behavior data and the determined at least one predefined carbon-saving quantity quantization algorithm. Based on the calculated carbon-saving quantity associated with the user and the user identification, user data is processed. The user data is related to the carbon-saving quantity associated with the user.

Abstract: A smart meal ordering method comprises: conducting body sensing of a diner by a body sensing hardware of a smart meal ordering device; outputting a meal ordering interface by a display screen of a smart meal ordering device in response to sensing that the diner has taken a seat, and obtaining information of one or more dishes selected by the diner on the meal ordering interface; and in response to sensing that the diner has left the seat, sending a total price of the dishes and identification information of the smart meal ordering device to a server.