Abstract: The invention discloses a challenge screening method for improving the stability of a strong Physical Unclonable Function (PUF). If the stability of the group of challenges (GOCs) is quantized by 1 or 0, the GOCs are defined as stable challenges or unstable challenges respectively; the GOCs and the stability of corresponding responses are defined as a challenge-stability pair (CSP); a machining learning training dataset is constructed through CSPs for obtaining a screening model, to associate the challenge stability with the screening model; during actual application of the strong PUF, the challenge stability of a strong PUF is determined through the screening model, and stable challenges of the strong PUF are screened out to form a stable challenge set, which is input into the strong PUF to extract identity information. The challenge screening method can effectively improve the stability of various strong PUFs and has better effect with external disturbance increasing.

Abstract: In a method for statistical analysis of aggregate encrypted data with key-leakage resilience for smart grids, every user area is managed by a fog node which plays the role of data aggregation gateway and data relay. All the users' electricity consumption data sent by smart meters in the same user area are firstly aggregated by the fog node to generate a fog-level aggregate ciphertext. Then the fog node further generates a digital signature for the fog-level aggregate ciphertext and sends these data to a cloud server for long-time storage. The cloud server stores all the aggregate ciphertexts and digital signatures received from different user areas in its database, and provides data query and statistical analysis services for the control center of smart grids. On the premise of without violating users' privacy, the cloud server could provide enough information for the control center, enabling it to compute the sum, arithmetic mean and variance of all users' data in specified areas in a privacy-preserving way.

Abstract: The present disclosure relates to an interaction method and apparatus, an electronic device, a readable storage medium, and a program product. The interaction method comprises: during the process of playing multimedia content, in response to a trigger operation for a target virtual gift in a virtual gift display interface, displaying a control component, and a first object and a second object which are comprised in the target virtual gift, wherein the control component is used for controlling a path for the target virtual gift; according to the state of the control component, determining a target path corresponding to the first object; and controlling the first object to move along the target path, and when the first object hits the second object during the process of movement, playing, at a position where the second object is hit, a first special effect corresponding to the second object.

Abstract: A strong and weak hybrid PUF circuit comprises N switch units and an arbiter. Each switch unit consists of two delay modules and two 2:1 multiplexers. The N switch units constitute two completely symmetrical delay paths. Each delay module consists of six stages of delay cells. During the operating process, a transmission signal selects a turn-on path of the corresponding 2:1 multiplexers according to activation signals; the switch units in the PUF circuit are in a valid state (if the delay modules are turned on) or in an invalid state (if the delay modules are not turned on) according to whether the delay modules are turned during the operating process; and the strong and weak hybrid PUF circuit can be flexibly configured to be of two different types (a strong PUF circuit and a weak PUF circuit) according to changes of the Hamming weight of input activation signals.

Abstract: Disclosed is an ML attack resisting method for a strong PUF. Response signals generated by applying multiple sets of different challenge signals to a strong PUF are used as information to be encrypted, and are put in order to form a plaintext matrix. Then a matrix multiplication operation is performed on two plaintext matrixes to generate a ciphertext matrix. Next, elements in a transform matrix obtained by performing binary transformation on the ciphertext matrix are used as final responses, which are in one-to-one correspondence with original challenge signals and are used as final CRPs of the matrix-encrypted strong PUF.

Abstract: This invention publishes a method for statistical analysis of aggregate encrypted data with key-leakage resilience for smart grids. In this invention, every user area is managed by a fog node which plays the role of data aggregation gateway and data relay. All the users' electricity consumption data sent by smart meters in the same user area are firstly aggregated by the fog node to generate a fog-level aggregate ciphertext. Then the fog node further generates a digital signature for the fog-level aggregate ciphertext and sends these data to a cloud server for long-time storage. The cloud server stores all the aggregate ciphertexts and digital signatures received from different user areas in its database, and provides data query and statistical analysis services for the control center of smart grids.

Abstract: A strong and weak hybrid PUF circuit comprises N switch units and an arbiter. Each switch unit consists of two delay modules and two 2:1 multiplexers. The N switch units constitute two completely symmetrical delay paths. Each delay module consists of six stages of delay cells. During the operating process, a transmission signal selects a turn-on path of the corresponding 2:1 multiplexers according to activation signals; the switch units in the PUF circuit are in a valid state (if the delay modules are turned on) or in an invalid state (if the delay modules are not turned on) according to whether the delay modules are turned during the operating process; and the strong and weak hybrid PUF circuit can be flexibly configured to be of two different types (a strong PUF circuit and a weak PUF circuit) according to changes of the Hamming weight of input activation signals.

Abstract: A method and apparatus for user status reminders in video communication, wherein the method may include: during a video communication procedure between a current user and another user, detecting, by monitoring, an intervening communication event; and sending a reminder message regarding the intervening communication event to the other user, the reminder message being operative to instruct as to whether the current user has a need to respond to the intervening communication event. Through technical solutions of the present disclosure, users participating in video communication may comprehend mutual status change conditions at any time, facilitating performing timely adjustments to the procedure and content of the video communication.