357results about How to "Improve concealment" patented technology

The invention relates to a micro-grid intelligent safety secondary voltage control method based on reinforcement learning, and belongs to the technical field of power grids. The method comprises the following steps: firstly, establishing a micro-grid secondary control model under hybrid network attack; a DoS attack defense network based on deep learning is designed, a self-adaptive FDI attack compensation state observer is designed, compensation for unknown FDI attacks is established, a self-adaptive law of compensation signals is designed, and estimation of the system state under network attacks is achieved. An evaluation-execution structure is constructed based on reinforcement learning, a virtual optimal controller and an actual optimal controller are designed in combination with a backstepping method, unknown parts in a system model, an evaluation network and an execution network are approximated by using a neural network, and a weight adjustment law is given. And introducing a log type barrier function into the performance index function, and constraining the output in a fixed constant interval to meet the constraint condition. The method can cope with DoS attacks and FDI attacks, and ensures stable control and safe operation of the secondary voltage of the micro-grid.

The invention belongs to the technical field of automobile information safety fuzzy testing, discloses an automobile information safety fuzzy testing method based on a large model, and develops optimization application research of LLMs in an automobile software fuzzy testing scene by utilizing the advantages of an artificial intelligence technology in the aspects of data processing, natural language interaction, generalization ability and the like. The concealment and effectiveness of the test set generated by the fuzz test are optimized, and the fuzz test process efficiency is improved. Through the implementation of the invention, related key technologies are applied to the fuzz test of the automobile, and other related products and enterprises in China are radiated by writing technical standards, so that the fuzz test system can be used as an application demonstration and sample plate of the fuzz test of the intelligent driving automobile. According to market analysis, fuzzy test calculation is carried out on 100 thousand automobiles every year according to the method, and the data safety and the system safety are improved.

The invention discloses a communication encryption method based on a two-dimensional inorganic / inorganic Van der Waals heterojunction polarized photoelectric detector, and belongs to the technical field of photoelectric devices. The photoelectric detector comprises a substrate, two-dimensional MoSe2 material layers, two-dimensional ReS2 material layers and a thin film electrode, wherein the two two-dimensional material layers form a Van der Waals vertical heterojunction and are of an II-type heterostructure; due to anisotropic light absorption of ReS2, effective carrier collection and transport capabilities of MoSe2 and an inhibition effect of heterojunction on dark current, the photoelectric property of the two-dimensional ReS2 / MoSe2 photoelectric detector is obviously improved, and meanwhile, the two-dimensional ReS2 / MoSe2 photoelectric detector has high responsivity of 89.4 A / W, fast response speed of 30.5 s and polarization sensitive characteristics, and can be applied to the field of photoelectric detectors. On the basis, information is subjected to multiple encryption by means of a polarization state information encryption technology, so that the concealment and security of an information transmission process can be greatly improved, and a new possibility is provided for the development of a security communication technology in the future.

The invention discloses a file transmission protection method, system and device based on multiple encryption algorithms, and relates to the technical field of information, and the method comprises the steps: selecting a target file needing to be transmitted, carrying out the preprocessing, and generating file fragments; analyzing the sensitivity of each file fragment, and performing hierarchical encryption processing to obtain an encrypted fragment set; selecting a steganography carrier file, and embedding the encrypted fragments into the carrier file to generate a steganography index table; generating a dynamic session key based on the confusion key pool, encrypting the steganographic file transmission layer and embedding a dynamic key generation parameter; the receiving end generates a session key according to the transmission message header, decrypts the transmission layer data, extracts the steganographic file and decrypts the steganographic file; recombining the decrypted and recovered fragmented data into a complete file according to an identifier sequence; by dynamically matching the steganography carrier file, the efficient embedding of the fragmented data and the generation of the steganography index table are realized, and the concealment and the adaptability in the transmission process are ensured.

The invention provides a safety protection method and device for an intelligent networked automobile, and the method comprises the steps: detecting a vehicle control abnormal instruction in a communication process between a target vehicle and a cloud end based on a vehicle control behavior characterization model and an abnormal behavior classification learning model; and based on the malicious traffic identification model, identifying hidden malignant traffic in the process of communication between the target vehicle and the cloud, through a deep reinforcement learning confrontation defense mode, a decision control model is trained according to a vehicle control abnormal instruction and hidden malignant flow, and the decision control model is used for carrying out safety protection on the intelligent network connection vehicle. Therefore, high-precision and high-reliability detection of attacks such as vehicle control instruction tampering attacks and strongly hidden malicious traffic under the intelligent network connection vehicle-cloud cooperation scene is realized, the attack concealment and attack efficiency are effectively improved, the robustness and generalization of the model are enhanced, and the method is suitable for the intelligent network connection vehicle-cloud cooperation scene. And the communication safety, the data safety and the driving safety of the intelligent networked automobile ecological system are improved.

The invention provides a cross-modal steganography method and device, equipment and a storage medium, and the method comprises the steps: inputting a carrier image and a ciphertext image corresponding to ciphertext text data into a preset encoder, enabling a learnable wavelet transform network and a reversible neural network in the encoder to carry out the forward feature extraction of the carrier image and the ciphertext image, and obtaining a feature extraction result; obtaining a target carrier feature vector corresponding to the carrier image and a target ciphertext feature vector corresponding to the ciphertext image; and generating ciphertext cross-modal steganography result data corresponding to the ciphertext text data based on the target carrier feature vector and the target ciphertext feature vector for network transmission. According to the method and the device, the ciphertext text data of the text mode can be embedded into the carrier image of the image mode, a multi-mode steganography technology is realized, the steganography concealment and robustness of the ciphertext can be effectively improved, and the ciphertext network transmission security and reliability can be further improved.

The invention relates to a watermarking method based on mutual information screening and IGWO optimization, and the method comprises the following steps: 1, carrying out the attribute screening through a mutual information method, obtaining an attribute set which is highly related to the classification accuracy, determining an unimportant attribute set, and forming a complete attribute set after the mutual information screening; step 2, based on the attribute set screened by the mutual information attributes in the step 1, carrying out watermark embedding operation for an unimportant attribute set to obtain a watermark data set containing a watermark; and step 3, based on the watermark data set generated in the step 2, watermark data are classified through a decision tree model, and the watermark embedding strength and position are optimized by applying an IGWO algorithm. The method can effectively solve the problem of traceability responsibility of matched power grid service data.

The invention discloses an inter-satellite link secure transmission method based on a hybrid covert strategy, and belongs to the field of electronic communication. According to the invention, more randomness and friendly interference are introduced from three layers of a network layer, an MAC layer and a physical layer, and potential eavesdroppers are confused; in a network layer, a random routing unit is adopted, a plurality of routing paths meeting communication requirements are dynamically selected to replace a single optimal path, and a selection probability is distributed to each routing path according to routing metrics. In the MAC layer, the spectrum sharing technology is utilized to distribute less power for the information needing to be hidden, so that the signal detection probability is reduced, and the communication security is improved. In a physical layer, a rate division multiple access unit and a superposition coding technology are adopted, so that a plurality of users can efficiently share the same time-frequency resource at the same time. According to the invention, the communication efficiency can be improved, and the transmission randomness and complexity can be further improved, so that the communication security is enhanced.

The invention belongs to the field of underwater bionic robots, and relates to a water-air cross-medium bionic robot which comprises a shell, a reciprocating swing mechanism, a wing module, a pelvic fin module and a control system, the shell comprises a front-end shell and a rear-end tail, the front-end shell is connected with the rear-end tail through the reciprocating swing mechanism, and the front-end shell is connected with the rear-end tail through the reciprocating swing mechanism. The wing module is installed at the top of the upper portion of the front-end shell, the pelvic fin module is installed on the rear side of the lower portion of the front-end shell, and the control system is installed in the front-end shell and connected with the reciprocating swing mechanism through a signal line to control the reciprocating swing mechanism to rotate so as to drive the tail of the rear end to swing to conduct cruise propelling and control the pelvic fin module to rotate to dive upwards and float downwards. The wing modules are controlled to be opened and closed to achieve water breaking gliding. The robot is compact in structure, small in size and light in weight, can achieve various motion postures in air and water, can meet application scenes in various environments, and particularly has high adaptability in the aspects of water-air cross-medium information collection and sending, information exploration and the like.

The utility model provides a positioning device. The positioning device comprises a shell, a shading block and a circuit module arranged in the shell, the circuit module comprises a first circuit board, a communication module, a positioning module, a control module and a light sensor, and the communication module, the positioning module and the light sensor are all in electric signal connection with the control module; the shell is provided with an installation face used for being attached to equipment to be positioned, a light through hole is formed in the shell wall, close to one side of the installation face, of the shell, the light sensor corresponds to the light through hole, and the light shading block is movably arranged in the light through hole to block the light through hole; when the shell is detached from the to-be-positioned equipment, the shading block is separated from the light through hole, the light sensor receives external light through the light through hole, converts a light signal into an electric signal and transmits the electric signal to the control module, and the control module controls the communication module to send alarm information to a mobile terminal of a preset emergency contact person. The positioning device provided by the utility model has a dismounting alarm function, so that the safety is improved.

The invention discloses a digital audio watermark processing method and device, equipment and a storage medium, and belongs to the technical field of artificial intelligence. The method comprises the following steps: receiving a watermark adding instruction, and carrying out Fourier transform on original host voice to obtain an audio signal; identifying a watermark information adding bit in the audio signal through the audio watermark model, and embedding a watermark message in the watermark information adding bit; the interfering audio signal and the audio signal carrying the watermark message are combined. Receiving the message extraction signal, and separating an interference audio signal in the combined audio signal; a watermark information adding bit in the audio signal is identified, and a watermark message is extracted from the watermark information adding bit. The invention also relates to the technical field of block chains, and the host voice is stored on a block chain network. According to the method, the watermark information adding position is automatically identified through the audio watermark model, so that the watermark information is added and extracted, the dependence on expert knowledge is remarkably reduced, and the watermark processing speed and efficiency are improved.

The invention relates to the technical field of medical drainage equipment, in particular to in-vivo effusion drainage equipment for breast surgery, which comprises a storage rack, a pair of drainage tubes and an overclothes for a patient to wear, two drainage bottles are placed in the storage rack, a box body is arranged at the top of the storage rack, and a driving mechanism is arranged in the middle of the interior of the box body; two first gas distribution mechanisms and two second gas distribution mechanisms are arranged in the box body and are symmetrically arranged relative to the driving mechanism. The first air distribution mechanism is driven by the driving mechanism to work to inflate and deflate the pressing air bag set, automatic pressing can be conducted on the mammary gland portion of an operation area of a patient, effusion can be rubbed away, accumulation of the effusion in mammary gland tissue is avoided, hematoma or blood clots are reduced, and the effusion is discharged more effectively; blood circulation and metabolism of surrounding tissues are promoted through pressing, swelling of an operation area is eliminated, postoperative pain and discomfort of a patient are relieved, swelling of the patient is relieved, and the healing process of the tissues is improved.

The invention relates to the technical field of network security and network simulation, and discloses a malicious traffic remodeling method based on feature serialization. The method comprises the following steps: collecting traffic data of a target network environment, extracting serialization features of a load and a time interval, and further performing statistics to obtain session flow features; according to Pareto distribution, normal distribution, logarithmic normal distribution and Poisson distribution probability distribution models, serialization features conforming to target network flow features are generated, and the probability distribution model with the highest similarity with the target network flow is selected by calculating the Euclidean distance; and finally, on the basis of the model, remodeling the load and time interval sequence of the malicious traffic, and generating the network attack traffic which is difficult to detect. According to the method, the concealment of the malicious traffic is effectively improved, so that the malicious traffic is more difficult to identify by an existing detection system; the generated malicious traffic can effectively test and evaluate the capability of the network intrusion detection system.

The invention discloses a multi-access-point covert communication federal optimization method for a UAV-RIS system. The multi-access-point covert communication federal optimization method comprises the following steps: (1) modeling aiming at UAV-RIS federal learning edge calculation; (2) modeling aiming at the UAV motion trail; (3) modeling is carried out for a UAV-RIS auxiliary hidden transmission channel; (4) formulating the problem; (5) decomposing non-convex problem form transformation and sub-problems; (6) carrying out splitting and form conversion on the sub-problems; (7) designing a dynamic cross optimization algorithm; according to the method, the covert communication federal learning has relatively high concealment and relatively high reliability.

The invention belongs to the technical field of launching of underwater unmanned aerial vehicles, and discloses a deceleration recoil resistance prevention device for complex water conditions. Comprising an unlocking assembly, a mounting assembly and a speed reduction assembly. A plurality of symmetrically-distributed electromagnets are arranged on the periphery of the unlocking assembly, the mounting assembly is fixedly arranged at the bottom of the unlocking assembly, and the positions, corresponding to the electromagnets, of the periphery of the mounting assembly are each provided with a speed reduction assembly; the speed reduction assembly comprises a swing rod, a wing piece, an unlocking iron plate and an unfolding spring. The swing rod is rotationally arranged at the bottom of the mounting assembly through a rotating shaft, the wing panel is fixed to the inner side of the swing rod, and the unlocking iron plate is arranged on the inner side of the wing panel, corresponds to the electromagnet in position and is used for attracting the electromagnet; the unfolding spring is fixed to the inner side of the wing piece and used for pushing the wing piece to be unfolded when attraction between the unlocking iron plate and the electromagnet is removed. According to the invention, the speed of the floating process of the preset platform can be reduced, so that the invisibility and stability of launching can be improved.

The utility model relates to a hidden multidirectional adjustable security camera, which belongs to the field of security cameras and comprises a mounting wallboard, a hiding mechanism convenient for mounting and hiding is arranged on the right side of the mounting wallboard, and security mechanisms convenient for multidirectional adjustable camera shooting are arranged on the inner walls of the upper side and the lower side of the hiding mechanism. The hiding mechanism comprises a fixing frame, a storage barrel, a fixing plate, a connecting plate, a positioning inserting ring and a decorative table lamp. According to the hidden type multi-azimuth adjustable security camera, the hidden mechanism is arranged, the fixing frame is a support installed on the right side of the wall plate and used for fixing the whole camera system, the storage cylinder is a part used for hiding the camera, and the camera can be hidden in the storage cylinder by being fixed to the inner wall of the installation opening; the connecting plate is connected with the fixing plate and the storage cylinder and plays a role in fixing the camera system, and the decorative table lamp is used for disguising the camera, so that the camera looks like a common lamp, and the concealment is improved.

The invention relates to the technical field of digital copyright protection and information security, in particular to a dark watermark generation system and method, and the system comprises an input data module, a robust feature extraction module, a self-adaptive dark watermark generation module, a deep learning embedding strategy module, and a dark watermark embedding module. Wherein the input data module is used for receiving digital content to be protected; the robust feature extraction module is used for generating feature parameters for embedding the dark watermark and determining a robust feature position; the self-adaptive dark watermark generation module is used for mapping the dark watermark information into a characteristic parameter space to generate self-adaptive dark watermark data; the embedding strategy module is used for generating a dark watermark embedding strategy; and the dark watermark embedding module is used for embedding the dark watermark data into the robust feature position of the preprocessed digital content. According to the invention, through combination of robust feature extraction, adaptive watermark generation and a deep learning embedding strategy, high precision and anti-interference performance of watermark embedding are realized.

The invention belongs to the technical field of nuclear power, and particularly relates to a black box transferable voiceprint recognition system attack resisting method and device based on frequency domain disturbance. According to the invention, the perception of the human ear on the voice signal is considered and simultaneously depends on the characteristics of the frequency and the loudness of the voice signal, and the adversarial disturbance is added in the frequency interval insensitive to the human ear, so that the voice adversarial sample generated by the method is hidden to the human ear, the human ear is difficult to distinguish, and the model classification is wrong; in order to solve the problems that most black-box countermeasure attack methods need to query a large amount of attack targets, the attack time is long, and practical application is difficult, the method utilizes the transferability of countermeasure samples, adopts a three-stage iteration method, and improves the concealment and generation speed of the countermeasure samples, so that a large amount of query of the attack targets is avoided, and the security of the countermeasure samples is improved. The method achieves the high-success-rate countermeasure attack for an unknown voiceprint recognition system.

The invention provides an adversarial sample generation method and device based on multi-feature saliency map fusion, and aims to generate an adversarial sample with relatively high quality. The method comprises the steps of obtaining multiple pieces of sample data, dividing the multiple pieces of sample data into a training set, a test set and a verification set, and selecting optimal model parameters through the training set, the verification set and the test set; inputting any original sample into an artificial intelligence model, respectively obtaining a first feature saliency map and a second feature saliency map based on an interpretability method of gradient and disturbance, and carrying out fusion enhancement on the first feature saliency map and the second feature saliency map to obtain an enhanced feature saliency map; performing truncation and normalization processing on the enhanced feature saliency map to obtain a processed enhanced feature saliency map; based on a global gradient attack algorithm, obtaining global adversarial disturbance of the original sample; performing superposition processing on the global adversarial disturbance and the processed enhanced feature saliency map to obtain local adversarial disturbance of the original sample; and adding the local adversarial disturbance to the original sample to generate an adversarial sample.

The invention discloses a robust feature-based physical world adversarial sample generation method, which comprises the following steps of: acquiring a pre-trained auto-encoder, three pre-trained image classification task models and a data set for an image classification task, setting attack parameters, and generating a robust feature-based physical world adversarial sample; an auto-encoder and three image classification task models are used to carry out iterative optimization processing on each image of which the category label number is t in the data set used for the image classification task, so as to obtain a robust feature code Ftar of the image of which the category label number is t; randomly selecting an image xc of which the category label number is c from a data set for an image classification task, initializing weight matrixes m and alpha, and respectively optimizing the weight matrixes m and alpha by utilizing robust feature codes Ftar of the selected image of which the category label number is v and the selected image of which the category label number is t; respectively obtaining optimized weight matrixes m'and alpha ', and obtaining a final adversarial sample according to the optimized weight matrixes m' and alpha '.

The invention relates to a sea-land-air triphibian aircraft which is composed of an aircraft head, an aircraft body and foldable wings, each wing comprises a fixing part, a folding part and a driving part, and unfolding and folding of the wings are controlled through hydraulic jacks. The aircraft is provided with a propeller engine and a propeller thruster which provide lift force and propulsive force respectively, and air flight, underwater navigation and land advancing are achieved. The driving system assembly comprises a submarine engine and an aircraft star-shaped engine, and the submarine engine is connected with and drives propellers to rotate through gears to provide power; the aircraft star-shaped engine is mainly used for air flight. The triphibian aircraft has multifunctionality, high flexibility and wide applicability, and is suitable for various scenes such as emergency rescue, military reconnaissance and environment monitoring. Special materials and design endow the robot with concealment and maneuverability, the robot can quickly respond and avoid potential threats during task execution, and the robot shows powerful comprehensive performance and wide application potential.

The present invention discloses a method for communication encryption based on a two-dimensional inorganic / inorganic van der Waals heterojunction polarization photodetector, which belongs to the technical field of optoelectronic devices. The photodetector includes a substrate, a two-dimensional MoSe2 material layer, a two-dimensional ReS2 material layer and a thin film electrode, and the two two-dimensional material layers constitute a van der Waals vertical heterojunction and a type II heterostructure; due to the anisotropic light absorption of ReS2, the effective carrier collection and transport capacity of MoSe2 and the inhibitory effect of the heterojunction on dark current, the photoelectric performance of the two-dimensional ReS2 / MoSe2 photodetector is significantly improved, and it also has a high responsivity of 89.4 A / W, a fast response speed of 30.5 µs and polarization sensitivity. On this basis, multiple encryption of information is performed with the help of polarization state information encryption technology, which can greatly improve the concealment and security of the information transmission process, and provide new possibilities for the development of future secure communication technology.

The frameless lamp with the night lamp comprises a lamp shell, a main lamp light-emitting assembly and a lampshade arranged below the main lamp light-emitting assembly, the lamp shell comprises a shell top and a connecting part arranged on the shell top, the lampshade comprises a bottom plate and a second annular wall extending upwards from the periphery of the bottom plate, and a clamping groove with an inward opening is formed in the inner side wall of the second annular wall. The shell further comprises a night lamp light-emitting assembly, a first annular wall extending downwards is arranged on the top wall of the shell top, the main lamp light-emitting assembly is arranged on the inner side wall of the first annular wall, and the night lamp light-emitting assembly is arranged on the outer side wall of the first annular wall. The night lamp function is added on the basis of the main lamp, the first annular wall allowing the main lamp and the night lamp to be installed at the same time extends downwards in the lamp shell, the main lamp and the night lamp share one lamp shell, and the lamp shell is simple in structure; the main lamp and the night lamp share the main lamp lampshade, the night lamp is hidden in the main lamp lampshade, the concealment is good, the night lamp and the main lamp have no obvious structural boundary, and the overall structure is more attractive.

The invention provides an underwater vehicle charging system and a charging method, and solves the problem that the loading capacity, the operation time and the operation flexibility of an underwater vehicle are affected as a heavy coupler needs to be carried at the vehicle end in the conventional underwater vehicle wireless charging system. According to the invention, the permanent magnet synchronous motor which must be carried by the underwater vehicle is used for energy supply, the battery of the underwater vehicle is directly charged through the electromotive force generated by the reverse rotation of the permanent magnet synchronous motor, and the situation that the load is increased by a coupler installed at the vehicle end in the conventional wireless charging process is avoided. The charging system comprises a charging device arranged underwater and a one-way clutch arranged between a transmission shaft of a permanent magnet synchronous motor of the underwater vehicle and a propeller. The charging device comprises a base platform, a mobile platform, a motor, a charging rod, a fixed electromagnet, a communication unit and a control unit. The motor converts electric energy obtained by the charging device into mechanical energy which is transmitted to the permanent magnet synchronous motor transmission shaft through the charging rod to drive the transmission shaft to rotate reversely.

The invention discloses a backdoor attack method for personalized federal learning based on feature aggregation, and belongs to the technical field of backdoor attack. The size of the designed back door trigger is equal to that of an input image, and each pixel value of the trigger is constrained. According to the design, detection based on image tampering defense can be effectively avoided, so that the backdoor trigger is more difficult to find visually. Secondly, training a backdoor trigger and a backdoor model by adopting an intra-class attack strategy; in the process, a backdoor trigger is trained by using a feature distribution alignment method, so that backdoor data generated by a malicious client is as close as possible to data distribution of other normal clients, and a federated defense mechanism based on model parameter clustering detection is avoided. And finally, all malicious clients cooperatively train a backdoor trigger. Feature aggregation of the backdoor trigger is carried out between malicious clients, data advantages mastered by an attacker are fully utilized, the generalization ability of the backdoor trigger is improved, and the backdoor trigger can still keep effective under wide input conditions.

The invention is suitable for the field of advertisement auditing, and discloses an advertisement content isolation auditing method, system and device and a medium, and the method comprises the steps: receiving advertisement content; the advertisement content is classified, and text advertisements, picture advertisements and video advertisements are identified and classified; the advertisement contents of different classifications are audited respectively; wherein when the picture advertisements are classified, digital watermarks are embedded in the picture advertisements, and the digital watermarks comprise category information of the picture advertisements. In the picture advertisement classification and auditing process, the digital watermarking technology is innovatively adopted in the picture advertisement classification and auditing method. By embedding the category information of the picture advertisement into the digital watermark and adding the watermark into the picture advertisement, quick classification and efficient management of the picture advertisement are realized, the accuracy and efficiency of picture advertisement classification are improved, convenience is provided for subsequent auditing work, and the user experience is improved. And the overall quality and efficiency of advertisement auditing are further improved.

The invention discloses a digital watermark camouflage method based on reverse information entropy tracking, which comprises the following steps: dynamically adjusting the embedding strength and the concealment of a digital watermark by monitoring the local entropy fluctuation of a signal in different processing stages, and monitoring the complexity of the signal through the local entropy change in the signal processing process, the method comprises the following steps of: extracting a variable quantity of a digital watermark, adjusting the camouflage degree of the digital watermark according to the variable quantity, adjusting key parameters in a digital watermark extraction and recovery process in real time through an information entropy feedback mechanism, optimizing the recovery precision of the digital watermark, and optimizing a digital watermark embedding process by adopting a reverse information entropy minimization method in a high-noise environment. And the anti-interference capability of the digital watermark under the noise interference condition is improved. According to the method, the digital watermark embedding and recovering strategy is dynamically optimized, so that effective recovery and stable transmission of digital watermark information are ensured under various noise and signal change conditions.

The present invention discloses a dual-branch generative adversarial watermark attack algorithm, which relates to the field of image processing technology and is characterized in that it comprises the following steps: S1: constructing a precise two-branch generative adversarial network architecture, including a detail-preserving generative adversarial network and a watermark attack generative adversarial network; S2: image difference analysis: using a precise two-branch generative adversarial network architecture to perform pixel-by-pixel difference operations between the original image and the watermarked image to extract image details and watermark information, and outputting two independent channels, namely, an image detail map and a watermark information map; S3: generating a detail-preserving image. The present invention can effectively counter existing watermarking technologies while maintaining image quality, provides a new tool for watermark security assessment, and promotes the advancement of watermarking technology.

The invention relates to an aircraft terrain clearance measuring method and system and a computer program product, and belongs to the field of signal processing. The method comprises the following steps: preprocessing received GNSS direct signals and reflected signals to obtain corresponding synchronous digital signals; according to the synchronous digital signals corresponding to the GNSS direct signal and the reflection signal, determining a waveform peak value position difference between the GNSS direct signal and the reflection signal; according to the waveform peak value position difference, determining a path delay difference between a GNSS direct signal and a reflection signal; establishing a signal reflection model of path delay difference and aircraft terrain clearance by combining terrain reflection characteristics, vegetation coverage and a mirror reflection geometric structure; and determining the terrain clearance of the aircraft according to the signal reflection model and the path delay difference. The method can be suitable for measuring the terrain clearance of the aircraft under different earth surface conditions, and has high concealment, accuracy and applicability.

The invention discloses a hidden gradient sample-based adversarial attack method and terminal, and the method comprises the steps: generating an adversarial sample based on an adversarial sample generation model and an original sample, calculating the training loss between the original sample and the adversarial sample according to a loss function of the model, and taking the training loss as a model gradient; according to the model gradient, selecting an original sample of a front preset proportion with the maximum model gradient as a hidden gradient sample, calculating the similarity between the original sample and the adversarial sample, and according to the similarity, screening hidden gradient samples with the similarity higher than a preset value from the hidden gradient sample set to form an attack sample set, by calculating the training loss between an original sample and an adversarial sample, samples which change drastically due to violent attacks can be determined, and then a high-similarity hidden gradient sample set is screened out from the hidden gradient sample set by calculating the similarity, so that targeted disturbance attacks are carried out on the hidden gradient samples, and the hidden gradient samples are subjected to high-precision disturbance attacks. Therefore, the attack concealment is improved while the attack resisting efficiency is improved.