61results about How to "Guaranteed certainty" patented technology

The invention relates to a functional security cloud platform and a control method for a rail transit real-time control system, the cloud platform follows a fault-security principle during design and meets the requirements of EN50129 functional security SIL4 level, and the cloud platform comprises a communication gateway used for providing a unified access entrance; the safe real-time virtualization system is used for virtual management, clock self-inspection and interrupt distribution; the security middleware runs in a virtual machine distributed by the security real-time virtualization system and is used for security clock verification, CPU memory self-check result verification, security communication, security voting, cycle control and application management; and the cloud management platform is matched with a virtual machine management module in the secure real-time virtualization system to jointly realize management of virtualization resources. Compared with the prior art, the method has the advantages of high safety, high reliability, high availability, high maintainability, high performance and the like.

The invention relates to the technical field of data transmission, in particular to an ink-jet printing data transmission system based on a TSN and an ink-jet printing system.The ink-jet printing data transmission system comprises a time-sensitive network switch used for receiving flow data frames sent by an upper computer; the time-sensitive network gateway is used for receiving the traffic data frame transmitted by the time-sensitive network switch, determining a transmission sequence of all traffic data in a preset transmission time window, and transmitting all processed traffic data; wherein the time-sensitive network gateway mathematical model is constructed based on the flow distribution balance optimization target and the system flow priority distribution optimization target by taking the total size of the flow data received by each electronic control unit as a constraint. According to the invention, the TSN technology is introduced, so that low-delay and high-determinacy data transmission under the condition of high bandwidth is realized in an ink-jet printing system; based on traffic optimization scheduling, a TSN traffic model is designed, a data transmission sequence is determined, and the flexibility and reliability of the system in the data transmission process are improved.

A numerical control wire feeding mechanism for an automatic wire penetrating numerical control wire cut electrical discharge machining tool comprises a base plate, a wire feeding wheel mechanism and a pressing wheel mechanism, the wire feeding wheel mechanism comprises a wire feeding wheel, a wire feeding wheel shaft, a driving gear and a wire feeding wheel driving mechanism, and the pressing wheel mechanism comprises a pressing wheel, a pressing wheel shaft and a driven gear. The mechanism comprises a main swing arm, an auxiliary swing arm, a main rotating swing shaft, an auxiliary rotating swing shaft, a main push pin, an auxiliary push pin, a push-pull block, a push-pull power mechanism and an elastic component. According to the scheme, the wire feeding wheel can be accurately fed to a fixed wire feeding position, the certainty of the wire feeding center position is guaranteed, the pressure of the pressing wheel on the electrode wire during wire feeding can be adjusted through the adjusting screw, and the requirement for automatic wire feeding is met. The defects that in the prior art, the wire feeding position is uncertain, the wire feeding pressure is inconvenient to adjust, the wire feeding wheel and the electrode wire are prone to slipping in the wire feeding process, and wire feeding is unreliable are overcome.

The invention relates to the technical field of seismic source fracture analysis, in particular to a seismic source time function extraction method and device, equipment and a storage medium. The method comprises the following steps: firstly, obtaining a station waveform record of a target earthquake, positioning each earthquake event associated with the target earthquake, obtaining a historical Green function of each earthquake event, and then applying a neural network model to the station waveform of the target event and each historical Green function to obtain each visual source time function of the target earthquake; and then carrying out convolution on the historical Green function and the apparent source time function, and screening and determining an optimal apparent source time function of the target earthquake according to a convolution result corresponding to each apparent source time function. According to the method, the target apparent source time function of the target earthquake is calculated through two deterministic parameters including the known station waveform and the historical Green function, and the whole process does not involve parameters needing manual adjustment or marking, so that the stability of the accuracy of the target apparent source time function can be ensured.

The invention relates to the technical field of networks, in particular to a network security system based on deep learning. A network security system based on deep learning comprises a data arrangement module which is used for updating virus data in a database and anti-virus software for processing the corresponding virus data, and obtaining data of each owned server. And the port detection and modification module is used for analyzing the dangerous data in the database by using a fuzzy reasoning algorithm based on the current server condition and the dangerous data in the database, combining the dangerous data with a traditional accurate control method to obtain an analysis result, and modifying the state of each port of the server according to the analysis result. According to the method, the database is updated by adopting big data, analysis is carried out according to the conditions of the servers and the access conditions of the ports, and whether the log data are normal or not is detected and judged by analyzing the log data.

The application relates to a control device and a control method for transmitting video data by using double-edge flip-flop, which comprises a video decoder chip and a video display interface chip, and a video signal selection device is arranged between the video decoder chip and the video display interface chip; the video signal selection device comprises a double-edge flip-flop and two two-way data selectors; a positive edge input end of the double-edge flip-flop is connected with an output end of the first two-way data selector; a negative edge input end of the double-edge flip-flop is connected with an output end of the second two-way data selector; and selection signal input ends of the two two-way data selectors are connected with sel signals. The control device and the control method for transmitting video data by using double-edge flip-flop adopt the double-edge flip-flop to generate DDR and SDR signals; no matter the DDR or the SDR signal, the last stage logic of the data output is fixed, the determinacy of input and output timing is ensured, the circuit is simplified, the transmission cost is reduced, and the video data transmission efficiency is improved.

The damping and buffering connecting mechanism comprises a switching assembly and a damping assembly, the switching assembly is arranged at the top end of a machine gun frame, the top of the switching assembly is connected with the damping assembly, and the top of the damping assembly is connected with the infrared sighting telescope; the adapter assembly comprises an adapter base, the adapter base is connected with an energy absorption adapter plate, and the energy absorption adapter plate is connected with a Picatinny guide rail piece; the damping assembly comprises a locking base and a locking bolt, the half side of the locking bolt is tightly embedded into the locking base, and the other half side of the locking bolt is tightly embedded into a transverse groove of the picatinny guide rail piece. The locking seat is connected with a connecting frame, and a damping shock absorber and a damping spring are arranged between the connecting frame and the connecting seat. According to the scheme, the shock absorption device has the beneficial effects that the structure is simple, the design is reasonable, and the shock absorption assembly is adopted to effectively protect the infrared sighting telescope, so that the shock absorption device adapts to the impact force of various machine guns with small and medium diameters, the use reliability of the infrared sighting telescope is improved, and the tactical application performance of the machine guns is powerfully ensured.

The invention provides a high and large formwork support design method based on a BIM technology. The high and large formwork support design method comprises the following steps that S1, a model is obtained; s2, generating a template; s3, performing analysis; s4, performing inspection; s5, generating a rule; s6, generating security information; and S7, output storage: storing the safety information report and the template support model in a database. According to the method, the inspected high and large formwork support model can be directly generated from the concrete structure three-dimensional model based on a rule generation mode, the labor cost of designers is greatly reduced, and the construction safety problem after the scheme is adopted is effectively ensured; the operation is simple and easy to adjust, the logic is clear and easy to implement, and the certainty of design can be effectively guaranteed based on a rule generation mode.

The invention relates to a signal processing method, device and equipment and a computer readable storage medium, and the method comprises the steps: obtaining the priority of a target signal when the target signal is received, setting a signal response thread for the target signal, and setting the priority of the signal response thread according to the priority of the target signal; wherein the higher the priority of the target signal is, the higher the priority of the corresponding signal response thread is, the signals are subjected to threading processing, each signal has one signal response thread with the priority, the signal response threads are added into the corresponding signal response thread groups, and the priority of the corresponding signal response threads is higher. The to-be-processed threads in the signal response thread group are sequentially processed according to the priority from high to low, so that non-emergency signals can be prevented from influencing processing of emergency tasks, the real-time performance of emergency signal response can be ensured, and the reliability, the certainty and the real-time performance of a real-time operation system are ensured.

The application relates to the technical field of electric digital data processing, and discloses an AI-based carbon data intelligent calculation operation system, which comprises a carbon tensor management module, a bypass scheduling module and a mapping processing module. The carbon tensor management module opens a non-paged continuous physical space in the memory to store time sequence energy consumption data flow. The bypass scheduling module acquires a server memory access topology map, identifies local memory nodes corresponding to different cores, and the mapping processing module extracts a topology boundary node and generates a kernel state topology boundary cut set according to a calculation topology correlation matrix. The operation system realizes physical image multi-projection mapping based on the topology map and the cut set, establishes a redirection path to convert remote memory access into local addressing access. The application eliminates hardware cache consistency detection signals through the image mechanism, solves a large-scale graph calculation memory access delay bottleneck, and guarantees calculation certainty.

This invention belongs to the field of daily chemical product testing and analysis technology. It discloses an intelligent screening method, device, equipment, and storage medium for sulfur / sulfonate surfactants. The method involves pretreatment of the sample and high-resolution mass spectrometry (UHPLC-MS / MS) scanning, converting the sample into an mzXML file. All secondary mass spectrometry peaks in the file are screened to identify target secondary mass spectrometry peaks containing characteristic ions. The mass and peak intensity of all corresponding precursor ions are extracted. If the mass difference between two precursor ions is within the range of sulfur isotope mass difference and the peak intensity ratio is within a specified range, the precursor ion with the lower mass is selected as the quasi-molecular ion. A predicted molecular formula is generated, and matching structural information is retrieved from a database. Simulated fragmentation is used to obtain a simulated secondary mass spectrum, which is compared with the actual secondary mass spectrum to determine the predicted structure and identify sulfur / sulfonate surfactants. This intelligent processing of high-resolution mass spectrometry data improves data processing efficiency, sensitivity, and accuracy.

The present application belongs to the technical field of remote controller automation testing, and relates to a communication and cooperative control method of a remote controller testing device and a production line system, comprising: the production line system acquires displacement sampling data and speed fluctuation coefficient, calculates compensation weight and determines cooperative reference time; the production line system acquires link transmission delay, generates a dynamic scheduling time slot of defining authorized sending time window at the data link layer according to the cooperative reference time, the compensation weight, the target work station coordinate and the link transmission delay, encapsulates the instruction containing the time slot into a data frame and issues it; the testing device analyzes the dynamic scheduling time slot, and when the clock value falls within the authorized sending time window, injects the testing result data into the network link, the present application compensates the displacement fluctuation in situ to the link layer scheduling algorithm, eliminates the phase slip of the communication period and the manufacturing beat, realizes the adaptive matching of the transmission right and the physical work station, and guarantees the transmission certainty.

The invention provides a folding device and electronic equipment, the folding device comprises a base, a connecting assembly and a supporting assembly, the connecting assembly is arranged between the base and the supporting assembly, one end of the connecting assembly is rotatably connected with the base, and the other end of the connecting assembly is rotatably connected with the supporting assembly; a track groove is formed in one of the supporting assembly and the base, a shaft part is arranged on the other one of the supporting assembly and the base, and the shaft part is matched with the track groove so that the folding device can be switched between the first state and the second state. The track groove is provided with a first end and a second end which are opposite, in the first state, the shaft part is located at the first end, and in the second state, the shaft part is located at the second end; the multiple track grooves and the multiple shaft parts are arranged in a one-to-one correspondence mode, and in the first state, gaps are formed between part of the shaft parts and the inner walls of the corresponding first ends. According to the folding device provided by the invention, the gap is formed between part of the shaft part and the inner wall part of the first end of the track groove, so that abnormal sound caused by friction between the shaft part and the track groove in the folding process can be avoided.

The invention discloses a man-machine interaction method and system based on MCP large language model dynamic graphical user interface generation, and relates to the field of man-machine interaction, and the method comprises the steps that an intelligent back end maps an identified user interaction intention into a structured MCP message frame through a protocol encoder; after the rendering front end receives the message frame, a virtual component structure tree is generated through strong type protocol specification verification, an interface updating patch is obtained through difference calculation, and a local component is dynamically instantiated to generate a real-time interaction interface; then capturing user operation, packaging the user operation into a state feedback message, returning the state feedback message to a rear end, triggering incremental reasoning of the model to determine whether to update an interface, and forming an intention-protocol-rendering-feedback interactive closed loop; according to the method, dynamic interaction of generation and evolution of a large language model interface along with natural language dialogue is achieved, the stability and safety of generation are improved through protocol layer strong verification, and low-delay response and deep man-machine cooperation are achieved through a difference rendering and event feedback mechanism.

This invention discloses an asynchronous sparse matrix outer product multiplier based on an event-driven circuit design. The multiplier employs a merging strategy that explicitly associates data with storage unit addresses, mapping matrix data address indices to corresponding addresses in the storage modules. Identical indices indicate identical storage locations, necessitating a merging operation. This strategy ensures the determinism of the data merging process and avoids complex sorting operations. Furthermore, the event-driven, clockless circuit used in this multiplier effectively mitigates some problems associated with synchronous circuits due to the absence of a clock and the use of an asynchronous controller to control data transmission. It also features low power consumption, high adaptability, and a certain degree of electromagnetic interference resistance, making it suitable for processing scenarios requiring ultra-low power consumption.

The invention discloses a TSN management method and device based on software definition, a medium and equipment, and aims to realize centralized configuration and scheduling of a TSN switch by utilizing a northbound interface and a southbound interface through coordination of a centralized controller and the TSN switch. The centralized controller allows remote access and configuration parameter modification through a northbound interface so as to generate a specific configuration instruction and a scheduling strategy, and it is ensured that the network carries out efficient scheduling and bandwidth allocation according to real-time requirements; and the southbound interface is used for issuing the configuration instructions to the switch and executing functions of clock synchronization, network state monitoring, forwarding and control separation and the like. In this way, seamless connection between different network technologies is achieved, the certainty of data transmission is guaranteed, and meanwhile the data processing capacity and the utilization efficiency of bandwidth resources are improved.

This invention relates to the field of Internet of Things (IoT) operating system technology and discloses a multi-terminal collaborative intelligent control system based on IoT, including multiple terminals, a motion execution module, and an edge control module. The edge control module reads the pulse count value of the motion execution module through memory mapping to determine the local displacement and extracts the logical timing code broadcast by adjacent terminals as an external reference. The edge control module compares the local displacement with the external reference to obtain the synchronization deviation. When the synchronization deviation exceeds a threshold, the edge control module generates a high-priority interrupt signal to modify the register instruction and corrects the weight based on the transmission timestamp difference to offset nondeterministic communication delay. This invention utilizes the collaborative determination of physical parameters and logical virtual parameters to construct a hardware-level security barrier, eliminate the interference of network jitter on motion timing, and ensure that the control beat is aligned with the execution beat.

The application relates to the technical field of electric digital data processing, and discloses a big data fast indexing and querying system based on general surgery diagnosis and treatment characteristics, which comprises a data stream acquisition module, a topological sequence reorganization module, a physical space mapping module, an index key synthesis module and a preloading execution engine; the topological sequence reorganization module analyzes heterogeneous diagnosis and treatment data streams and reorganizes the data streams into logically continuous patient whole-course data aggregates; the physical space mapping module sequentially maps the aggregates to a continuous physical address space of a bottom-layer storage; the index key synthesis module generates composite index items according to physical address offsets among data blocks; and the preloading execution engine drives the bottom-layer storage to burst read, the application converts cross-modal diagnosis and treatment correlation queries into one-way sequential reading of the storage, reduces the track delay and access overhead in the searching process, and guarantees the searching response delay certainty under the condition that the data volume continuously grows.

The present invention discloses a crane winch mechanism with good safety, which relates to the technical field of winches; in order to solve the problem of fatigue damage; specifically comprises a frame and a winding and releasing part, a safety anti-collapse part and a cable arrangement part respectively arranged on the outer wall of the frame, the winding and releasing part comprises a drum part, a drum reducer for controlling the winding radius of the drum part and a driving part for driving the drum part, the drum part comprises a base drum and a circular array of fan-shaped drum units arranged on the outside of the base drum, the fan-shaped drum unit is slidably connected to the outside of the base drum through a limiting column, the drum reducer comprises a ladder limiting shaft sleeve which cooperates to be limited on the inner side of the limiting column and is rotatably connected to. When the present invention is in a non-winding state, the reaction force is small, and at this time the stress of the stranded rope will exert a radial force on the fan-shaped drum unit, thereby sliding the fan-shaped drum unit inward, making its radius smaller, thereby offsetting the internal stress of the stranded rope and preventing fatigue limit damage.

This invention proposes a global parameter configuration method based on parallel discrete event multi-process simulation. This method achieves bidirectional handshake interaction between the host configuration software and the simulation platform software through a Socket transmission interface, mutually verifying the initialization status and automatically restarting the corresponding software initialization process in case of initialization errors. The simulation platform software aggregates all process local parameters and reports them to the host configuration software, which then generates a unified format global parameter file. After the simulation platform software sends a distribution request, the host configuration software distributes the global parameter files sequentially according to the process number. The simulation platform software collects the file reception identifier and process parameter configuration identifier of each process for hierarchical judgment, distinguishing between file reception failure and parameter configuration abnormality, and performs targeted retries for repair. After all processes pass verification, the parallel discrete event multi-process simulation is started. This invention solves the problems of complex global parameter configuration, difficult synchronization, and cumbersome fault handling in existing parallel simulations.

The invention discloses an edge deployment-oriented neural network video coding model lightweight method, which comprises the following steps of: constructing a video compression model as a reference model to be optimized; inserting a dry mask layer which can be trained into a preset position of a reference model to be optimized, and performing joint training on mask parameters by utilizing a sparse loss function and rate distortion loss to obtain mask parameter distribution; when the proportion of the mask parameter compressed to be zero in any mask layer reaches a preset target sparsity, sparse updating of the corresponding mask layer is stopped, and a mask layer state reaching a sparsity target is obtained; performing fusion operation on each mask layer and the adjacent network layer to obtain a neural network model after structure compression; and removing all mask layers to obtain a lightweight video coding model, and deploying the lightweight video coding model on edge equipment to execute a video compression task. According to the method, the model complexity can be greatly reduced, and the reasoning speed and the deployment efficiency of the edge equipment are improved.

This invention relates to the fields of medical informatics and data communication technology, specifically a CRRT online acquisition and intelligent monitoring system based on HL7. The system includes: a protocol cleaning and state mapping step: parsing the private protocol binary stream based on a virtual device state machine model to extract the device operating status and monitoring value vectors; a differential semantic analysis step: calculating the rate of change and deviation vector of the monitoring value vector relative to the historical time window; an adaptive message encoding step: selectively generating incremental maintenance messages or full semantic messages based on the comparison results of the rate of change and semantic fluctuation threshold; and a hybrid channel transmission step: dynamically allocating transmission channels and error correction coding strategies according to the message type to execute transmission. This invention solves the transmission contradiction between the real-time nature of high-frequency vital sign data and the redundancy of standardized protocols, balancing standard compatibility and real-time alarm capabilities under limited network conditions.

The application provides a laser transmission method and system for atmospheric turbulence adaptive compensation, and relates to the technical field of optical communication. A distorted laser beam is received by a receiving aperture and physically split for detection, and an instantaneous sequence of light intensity, a two-dimensional tilt vector in time domain and a residual high-order phase array are synchronously extracted. The tilt vector is converted into a low-order control instruction in a first control period, the residual high-order phase array is corrected by a physical wind speed feedforward in a second control period and converted into a high-order control instruction, and the stroke saturation and the physical driving voltage saturation are output at the end of the period. The light intensity sequence is collected to calculate a light intensity flicker index, a multi-dimensional channel state matrix is constructed by combining the bit error rate, the stroke and the voltage saturation, a three-state transfer decision is made according to the relationship between the numerical value of the elements in the matrix and a preset threshold, and finally, corresponding communication modulation format switching and receiving aperture physical adjustment are performed according to the decision result, so that time sequence decoupling and cross-layer linkage are realized, and the strong turbulence link breakage rate is greatly reduced.

The invention discloses an execution list merging method and device, equipment and a storage medium, relates to the technical field of automation, and discloses an execution list merging method which comprises the steps that in response to a trigger request for receiving a to-be-merged list, the remaining duration for triggering a recent event in the current execution list is checked; judging whether the residual duration is smaller than a merging duration of a preset merging period or not; if it is determined that the time length is less than the merging time length, delaying the trigger time of each event to be merged in the list to be merged based on the merging time length, and determining a corresponding delay time; and in a preset merging period, according to the delay time, merging the to-be-merged events into a current execution list. Namely, the triggering time of each to-be-merged event is delayed through the set merging duration of the preset merging period, so that the certainty of the triggering time of each to-be-merged event is ensured, and then in the preset merging period, the to-be-merged events are merged into the to-be-executed list according to the triggering time, so that the resource access conflict generated in the merging process is avoided.

The present application relates to finite time reduced dimension observer design method and chaotic communication system, belong to information security and chaotic communication field. In view of the defects of traditional asymptotic observer slow, time is uncontrollable, sliding mode method exists chattering and message signal pollution output is difficult to construct observer, the present application establishes the chaotic drive system containing message signal embedding, constructs the equivalent system without unknown signal, designs finite time reduced dimension observer based on observer matching condition and strong observable condition. Compared with the traditional asymptotic convergence observer method, the present application can realize the complete synchronization of chaotic system within the user preset time, adopts continuous control law without chattering, and the message signal can be accurately recovered through algebraic formula. The synchronization time of the present application is controllable, the convergence speed is fast, the recovery precision is high, and the robustness is strong, which is suitable for various chaotic secure communication scenes, effectively improves the communication real-time, security and engineering practicability.

The invention discloses a flow table state synchronization and packet processing method based on an intelligent network card, and belongs to the technical field of computer network communication, and the method comprises the steps: obtaining flow table item meta-information, local historical matching data and an external state prompt signal, and generating multi-dimensional prediction input; based on the multi-dimensional prediction input, a synchronization urgency index is obtained through calculation of a local flow table behavior predictor, and a precise synchronization request is generated and sent according to the synchronization urgency index; performing arbitration processing based on the local flow table mirror image and the shadow flow table area on the received data packet to generate a data packet processing result; and receiving pre-execution confirmation feedback generated based on the data packet processing result, and adjusting the calculation parameters of the local flow table behavior predictor according to the pre-execution confirmation feedback, so that the low-delay consistency synchronization of the flow table state and the continuous linear speed processing of the data packet can be realized while the control signaling overhead is remarkably reduced.

The application discloses a kind of financial amount writing compliance audit and positioning method, system based on multimodal big model, storage medium and electronic equipment. Including: obtaining image;Multimodal big model training, learn the decision boundary of rejection automatic correction;End-to-end feature extraction, without character segmentation, generate structured audit results: output original text sequence, do not automatically correct non-standard character;Generate corresponding standard text sequence;Map out the pixel coordinates of error character in original graph;When determining that there is writing error, infer the lower amount value based on standard text sequence, and mark as inference result.The present application effectively overcomes the pain points such as traditional OCR covering non-compliance risks due to excessive correction, segmentation failure caused by handwriting, lack of logical verification and inaccurate error positioning, etc., achieving the beneficial effects of preserving original physical evidence and outputting correct amount while accurately positioning error pixels.

The invention relates to the field of data transmission, in particular to an ultra-low time delay data transmission system based on the TAN technology, which comprises a multi-path controller, and the multi-path controller is connected with application equipment and a service terminal; the multi-path controller comprises a data processing module, a dual-channel framework module, a multi-path transmission module, an intelligent routing module, a precise time service module, a network observation module, a data mirroring module and a security technology fusion module. The time clear network technology is applied, the problems of ultra-low time delay and deterministic zero-cure characteristics of network transmission are solved, and the security of the network transmission is improved. And bidirectional interactive transmission of the intelligent power grid is realized.

The invention discloses air transportation container intelligent storage equipment with an automatic locking and clamping mechanism, and relates to the technical field of transfer devices. The air transportation container intelligent storage equipment with the automatic locking and clamping mechanism comprises a second cross beam frame, a first transfer assembly, a second transfer assembly and a fixing assembly. The first transfer assembly is arranged on the second cross beam frame, the first transfer assembly comprises a second transmission device and two guide parts, the second transfer assembly is arranged below the second cross beam frame, and the second transfer assembly comprises a first pulley, a traction rope, a first transmission device, a base, a first cross beam frame and a guide base. The second transmission device of the first transfer assembly on the right side can transfer the aviation case to the second transfer assembly, then the second transfer assembly drives the aviation case to move to a proper position, then the first transfer assembly is matched, the aviation case is placed at the proper position, and manual carrying and the like are not needed in the whole process.

The invention relates to the technical field of aviation aircraft design, and discloses a variable camber wing based on a bistable composite material structure driving multi-section rotation, which comprises a wing leading edge structure, a multi-section rotation rigid skin, an internal truss structure connected with the multi-section rotation rigid skin, a bistable composite material driving structure and a transmission mechanism, the bistable composite material driving structure is arranged between the rigid skin hinge and the transmission mechanism; and the transmission mechanism is arranged between the truss structure in the rigid skin and the sliding chute of the wing leading edge structure. The control precision and reliability are improved through relative change of the three rigid wings, and the problems that in the prior art, the structure is complex, the weight is large, the actuation efficiency is low, and the bearing capacity is low are solved.