274 results about "Design speed" patented technology

A system for testing a high speed integrated circuit includes a test device having a test clock with a first maximum frequency for performing level sensitive scan design (LSSD) testing of the integrated circuit device under test, a frequency multiplier circuit for multiplying the test clock signal to a higher second frequency capable of operating the device under test, and a finite state machine for generating a first internal clock for testing the device under test. In a practical embodiment, the internal clock speed may be running at a frequency many multiples of the test clock. Alternatively, a method of testing a device under test (DUT) at design speed includes running a predetermined group of tests with a test device operating at a lower speed than the design speed; incorporating LSSD or boundary scan test techniques in the device under test, together with a frequency multiplying device; generating a global clock for the device under test from the frequency multiplying circuit and using a finite state machine as a synchronizer and pulse generator to control a capture clock with respect to the global clock.

Probe data collected at times of low traffic density is analyzed to derive a Raw Road Design Speed Limit (RRDSL, 16) for each road segment or group of segments in a digital map. The RRDSL (16), comprised of longitudinally distributed Pt speeds, is associated with the road segment and stored in a digital medium to indicate the limits of the road section in free flow traffic. The longitudinally distributed speeds may be limited by local speed limits or other business logic to establish a Legal Raw Road Design Speed Limit (LRRDSL, 17). Either the RRDSL (16) or the LRRDSL (17) can be further modified to smooth acceleration and deceleration rates between changes in the longitudinally distributed speeds to create an Optimal Longitudinal Speed Profile (OLSP, 18), which represents optimized energy consumption. A signal can be produced if a driver's current speed rises unacceptably above a longitudinally distributed speed in real time. The signal can be audible, visible and/or haptic. Real-time traffic density information can be inferred by comparing current speed data to the longitudinally distributed speed for that position. If the current speed is consistently lower than the longitudinally distributed speed for that position, an inference is drawn that the road section is inefficient. Road efficiency assessments can be transmitted to a service center and/or other vehicles, and used by navigation software.

An engine starting system for a rotary wing aircraft includes a controller that receives a signal indicative of a start command for an engine, a transmission input module that is mechanically coupled to a transmission system and an accessory gearbox and a starter motor that is mechanically coupled to a compressor drive shaft of the engine. Also, a method for restarting an engine in flight includes receiving by a controller a signal indicative of a start command for the engine, determining by the controller that an overrunning clutch is coupled to the engine, transmitting by a transmission system motive power to the engine in response to the determining that the overrunning clutch is coupled to the engine and driving via a compressor drive shaft a compressor section of the engine according to a design speed.

The invention provides an expressway black spot identification system and method, and belongs to the technical field of road safety evaluation. Based on a TRANSCAD geographic information system, expressway conditions, traffic conditions and historical accident data are integrated to provide a grading method of safety service levels, and expressways with different lanes and different design speeds are divided into four safety levels via the relation between the traffic volume and the number of accidents, so that the technical method system of expressway safety evaluation is enriched; a black spot identification method integrating safety service level and quality control is proposed, so that the disadvantages of single evaluation are effectively avoided, and the fairness of relevant evaluation is improved; and the system and the method effectively improve the normalization of expressway traffic data and accident data management, improve the black spot identification efficiency and practicability, improve the expressway safety level, can import other expressway data according to road pile numbers at any time, and are based on the framework of the system.

A thin-type heat pipe structure includes a flat pipe, a second capillary structure, a third capillary structure, and a working fluid. The flat pipe has two boards and a containing chamber. A first capillary structure is set on the inner surface of the boards. The second capillary structure is contained in the containing chamber and covers a part of the first capillary structure. The third capillary structure is a stripe, contained in the containing chamber and clipped between the second capillary structure and another part of the first capillary structure. The working fluid is filled in the containing chamber. The overall design speeds up inner air's outflow and inner liquid's backflow.

The invention discloses an under-actuated water surface ship control method satisfying preset tracking performance. Aiming at an under-actuated water surface ship nonlinear dynamic model, tracking error steady state precision and a transient state performance index are designed, a transverse function is built to introduce extra control input, and design of a tracking controller is completed, thereby ensuring that a tracking error of a closed-loop control system converges to a preset arbitrarily small area, and ensuring that the convergence rate and overshoot satisfy preset requirements. The method specifically includes the following steps: establishing an under-actuated water surface ship dynamic model; designing steady state performance and transient state performance requirements of a control system; designing a speed error equation to introduce extra control; designing a disturbance observer to compensate external time-varying disturbance; and designing a state feedback tracking controller. The control method designed by the invention can solve the problem of under-actuated water surface ship motion control, realize tracking control of any smooth reference trajectory, and improve tracking error steady state performance and transient state performance of the control system.

The invention discloses a spacecraft attitude stability control method by using a biasing tether. The method comprises: a system dynamics model is established; a nonaffine non-linear system model is converted into an affine non-linear system model; speed information is used as a virtual control value and a controller is designed; the designed virtual control value is used a control instruction and a speed/angular speed controlled is designed; and an anti-saturation module is added into the controller and an influence caused by movement limitation of a tether connecting point can be suppressed. According to the invention, on the basis of movement of a biasing tether point, an attitude of a capture mechanism is controlled, thereby substantially reducing fuel consumption of the capture mechanism during the operation task process. In addition, the nonaffine non-linear system model is converted into the affine non-linear system model by means of first-order taylor expansion and that the similarity and error meet the Lipschitz condition is demonstrated; and when the system design is controlled, an adaptive compensation item compensation module error is designed. The method is simple and the practicability is high.

The invention provides a multi-AUV formation optimization control method under an obstacle environment, and belongs to the technical field of ship control. A path tracking error model is established based on a sight distance navigation method, a path tracking controller is designed by adopting a feedback linear method, a multi-AUV communication topological relation and a coordination error model are established by utilizing a graph theory, and a speed coordination controller is designed, so that the formation control is achieved, and a formation optimization obstacle avoidance strategy considering the environment constraints is designed according to the obstacle environment, the optimal formation topological structure is obtained through solving the environment fitness function, so that the formation can pass through the region in the obstacle environment in an optimal formation mode.

The invention discloses an entropy coder for a video coder and an implementation method thereof. The implementation method of the entropy coder comprises the following steps: mapping each coding functional block of the entropy coder of the video coder into hardware logic description which is composed of operator units, wherein each coding functional block is described by an advanced program language algorithm; and generating a hardware integrated circuit of the entropy coder by the hardware logic description which is composed of the operator units. According to the invention, the design speed for the integrated circuit of the entropy coder can be quickened.

The invention discloses an accurate control method for a path tracking of an unmanned ship based on a dual guidance of the speed and the heading. The method comprises the following steps of: establishing a kinematics model and a dynamics model of the unmanned ship; constructing an error dynamics of the path tracking; designing a dual guidance law of the speed and the heading; and designing a finite-time interference observer. According to the accurate control method for the path tracking of the unmanned ship based on the dual guidance of the speed and the heading, the dual guidance law of thespeed and the heading provided by the control method can simultaneously guide the speed and the heading angle according to the path tracking errors, and improves the stability and flexibility of the path tracking control system. The finite-time interference observer constructed by the control method can accurately observe the complex external disturbances; ensures that the observation error is zero for a finite time; and can avoid the limitations of bounded observations and asymptotic observations. The control method designs a speed and heading tracking controller combining the design of a finite time observer and the back stepping control technology, so that the guidance signal can be accurately tracked in the presence of a complex interference, thereby achieving the accurate control forthe path tracking of the unmanned ship.

The invention discloses a deep collapsible loess subgrade structure, which can strictly control the post-construction settlement and differential settlement of the collapsible loess and the deep collapsible loess foundation. It includes reinforced concrete pile foundations (10), which are arranged in groups at intervals along the longitudinal direction of the foundation, and the pile bodies are consolidated with the bearing layer after penetrating the soil vertically; The top of the foundation (10) is rigidly connected thereto; the reinforced concrete cap slab (30), extending longitudinally along the foundation, is supported on and connected to the reinforced concrete joist (20). The invention uses the pile-slab system as a reinforcement structure, which has the characteristics of strong adaptability, good overall performance, high rigidity, small deformation, large depth of untreated soil, and convenient construction, and successfully solves the problems of uneven settlement caused by collapsing The technical problem of excessive settlement can well meet the design requirements of passenger-dedicated railways with a design speed of 300-350 kilometers per hour.

The invention relates to a method for determining the resilience modulus parameter of the soil foundation of a road, comprising the following steps: (1) determining the stress level [theta, tauoct] and the compaction degree range CD of the soil foundation of the road according to the road grade and the typical road surface structure; (2) in the passing area of the road, selecting the typical soil sample of the soil foundation of the road, and detecting the physical indexes including the liquid limit and the water content of the typical soil sample; (3) calculating the range [ki1 ki2] (i=1, 2 and 3) of a model parameter ki according to the step (2) throughthe estimation formula of the model parameter ki; and (4) calculating two resilience moduli of the soil foundation of the road according to the step (2) and the step (3) through the estimation formula of the resilience modulus of the soil foundation of the road. Due to the adoption of the technology, the resilience modulus of the soil foundation of the road can be obtained quickly, the cost and time spent doing dynamic triaxial test are saved, the test doing complexity, the difficulty of obtaining the resilience modulus parameter value and the test engineering amount are reduced, the design speed is increased, and the design cost is saved.

The invention relates to a traffic signal coordinated control device with a plurality of intersections, in which the system model 'green wavestrip'is not straight line but broken line and the ratio between inner trajectory slope of intersection and trajectory slope on the road equals coefficient of dampling of the said intersection. The device is provided to treat the design speed of the vehicles on the ground and inside the crossing in a same way. The device consists of a device of variable proportions, in which the device uses different scales to different components with a same length of oriented path: the ground lengths among crossings keep normal proportion of true size, but the measurement of the ground design length of gross ditch inside the crossing enlarges a multiple which is homologous to the coefficient of damping of crossing compared with measurement of the ground actual length of gross ditch inside the crossing, then drafts according to a normal proportion.

The invention provides an information acquisition release system and a method for guiding a left-hand turning vehicle to pass through an intersection. The system comprises a central control unit, a first sensor, a second sensor and a display device, the central control unit is respectively connected with the first sensor, the second sensor and the display device and used for processing traffic information, the first sensor is located at a T*V distance position of an opposite through lane stop line and used for acquiring entry time point and driving speed of a straight driving vehicle which enters into the intersection, the T represents an absolutely safe vehicle clearance, the V represents a design speed of the road where the vehicles drive, the second sensor is located at a position of the opposite through lane stop line and used for detecting straight driving vehicles which pull out, and the display device is used for displaying opposite through lane vehicle information. By means of the system and the method, suggestion information is provided for the left-hand turning vehicle to determine the left-hand turning, a left-hand turning driver can be aided in determining vehicle clearances of the straight driving vehicles, the traffic capacity of the intersection is improved, and dangerous conflicts between the left-hand turning vehicle and the straight driving vehicles are reduced.

The invention relates to a module power supply standard design system, and a design method and application thereof. A power supply product standard design system comprises a template base, a typical circuit base, an element base, a typical circuit calling module, a wiring diagram conversion module, a cable management module, an element directory generating module, a PCB (Printed Circuit Board) routing diagram generating module and a PCB assembling diagram generating module. Meanwhile, the design method of the module power supply standard design system is provided; a typical circuit can be directly called; a wiring diagram, a conducting wire table, an element directory, a PCB routing diagram, a PCB assembling diagram and a general detailed table are automatically generated; the design time of a designer is shortened; the design efficiency is improved; and the conditions of conducting wire table and wiring diagram inconformity, element lack and the like due to human negligence are avoided. Meanwhile, a method for performing power supply product design by using the standard design system is provided. The standard design of a power supply product is realized; the design speed is high; and the product quality is high.

The speed limit of a vehicle should ensure the efficiency and the safety, but an interactive relationship exists between the efficiency and the safety. Based on the safety constraint conditions, the invention comprises the following five steps: 1. establishing a limit speed model with respect to the safety based on the principle that the speed limit on a highway should ensure that the accident death rate is less than an acceptable tolerance value; 2. determining the limit speed and a 85% speed relation model; 3. establishing a traffic accident prediction model; 4. quantifying the traffic safety service level, wherein the accident rate is used as an index for quantifying the safety service level; and 5. establishing a time-cost function of a high-grade highway based on the 85% speed and the design speed, and establishing an objective function of the operating efficiency by using the minimum time-cost. The invention establishes a limit speed optimization model using the operating efficiency as the objective function, and can calculate the optimum speed limit in the specific benefit orientation by using the limit speed optimization model.

The invention discloses a deblocking filter for a video coder and an implementation method thereof. The method comprises the following steps: mapping each filtering function of the deblocking filter of the video coder described by the high level program language algorithm into the hardware logic description formed by operator units; and generating a hardware integrated circuit of the deblocking filter by the hardware logic description formed by the operator units. By applying the invention, a system engineer can realize fast mapping from the deblocking filtering algorithm described by the high level language to a hardware circuit at the lower layer according to a complete operator cell library capable of supporting the description of the high level language algorithm, thereby finishing the fast design of the deblocking filter integrated circuit. Moreover, the deblocking filter and other application specific integrated circuit (ASIC) parts in the video coder can perform parallel flow operation, thereby increasing the design speed of the ASIC of the video coder. The deblocking filter can be suitable for different video coder structures and has good universality.

(A2) A turbofan engine control system for managing a low pressure turbine speed is provided. The turbofan engine control system includes a low spool having a low pressure turbine that are housed in a core nacelle. The low pressure turbine is adapted to rotate at a speed and includes a maximum design speed. A turbofan is coupled to the low spool. A fan nacelle surrounds the turbofan and core nacelle and provides a bypass flow path. The bypass flow path includes a nozzle exit area. A controller is programmed to command a flow control device adapted to effectively decrease the nozzle exit area in response to a condition. Reducing the nozzle exit area, either physically or otherwise, maintains the speed below the maximum design speed.

The invention discloses a method for calculating the traffic capacity in a city expressway entrance interlacing region, and aims at filling a gap that there is short of a calculation method for effectively estimating the traffic capacity. The method comprises the following steps: 1, collecting related traffic parameters of an expressway interlacing region: 1), the mean time headway (shown in the description) of the traffic flow of an expressway trunk line Ls; 2), a critical time gap tC which allows ramp vehicles to merge into the expressway trunk line Ls; 3), the time headway th between two ramp vehicles; 4), the flow Q of the expressway trunk line Ls; 5), the distance L between a nasal tip N and a merging point of an accelerating vehicle La; 6), the design speed V1 of the expressway trunk line Ls; 7), the design speed V of a ramp; 2, calculating the probability distribution parameter K of the time headway of the expressway trunk line Ls; 3, building a method for calculating the traffic capacity of the ramp R; 4, improving the method for calculating the traffic capacity of the ramp R; 5, calculating the traffic capacity of the interlacing region through employing a formula (shown in the description), wherein CM is the traffic capacity of the interlacing region, the unit is vehicles/hour, and delta t is the time different of the ramp vehicle M2 and a trunk line vehicle M1 (unit is second).

The invention relates to a design method for stiffness matching and diameter of vehicle suspension stabilizer bars and belongs to the technical field of vehicle suspensions, aiming to fill a gap of the reliable optimal design method for diameter of the stabilizer bars due to limitation of radial deformation analytic analysis and inter-coupling of the stabilizer bars and rubber bushings. The design method is characterized by including the steps of firstly, performing matching design on stiffness of angle of roll of a front suspension stabilizer bar system and a rear suspension stabilizer bar system according to vehicle parameters and roll models; secondly, building an optimal design mathematical model of the stabilizer bar diameter d according to the matching design value of stiffness of the angle of roll, the radial stiffness coefficient Kx of the rubber bushings and the deformation coefficient expression Gw of ends of the stabilizer bars so as to obtain the accurate and reliable optimal design value of the stabilizer bar diameter d by means of a Matlab program. By the design method, design level and performance of the suspensions and the stabilizer bars can be improved, riding comfort and safety of vehicles can be improved, and meanwhile, design speed for product development can be increased and cost for design and test can be reduced.

The invention discloses a road horizontal curve radius design scheme security assessment method based on virtual vehicle rollover and sideslip tests. The method comprises the following steps of defining a control function used for assessing a target road; constructing a driver- heavy truck-target road virtual test simulation platform by using adams/car; acquiring a dynamic index of the heavy truck running on the target road at a designed speed v according to the virtual test simulation platform, and computing values of LTAr and LTRr; and judging whether the computed values of LTAr and LTRr meets the requirements of a control function F(r). According to the method provided by the invention, the moving state of the vehicle passing through a curve can be more accurately acquired, and an assessment result is acquired by rapid quantitative computation; the method can be applied to the roads in various stages, thus being wide in application range; by using the method to road horizontal curves in design and construction stages, dependency on real operation data of the roads can be avoided.

The invention relates to a burst speed simulative analysis method for a bolt-free structure turbine disk baffle. The method comprises the following steps: establishing a two-dimensional section model capable of accurately reflecting a blisk structure form; arranging an elastic material model; according to model features, creating an axial symmetric unit and a plane stress unit; setting a boundary condition and a load; calculating solving parameters; judging whether a solving process is converged or not; if the solving process is converged, performing post-processing to output a stress calculation result; and according to a burst criterion, calculating a baffle burst speed. According to the method, the burst speed simulative analysis is carried out for the bolt-free structure baffle, so that the baffle is ensured to work safely and reliably within a design speed range, the hidden troubles of faults in aero-engine design are reduced, and decision bases and technical support are provided for analyzing occurred engine shroud faults.

The invention discloses a hypersonic aircraft self-adaptation time-varying preset performance control method based on LS-SVM. The method includes the steps of firstly, designing LS-SVM identifier and a time-varying preset performance function according to the longitudinal model of an air-breathing hypersonic aircraft to obtain an error transformation model; secondly, designing a speed subsystem self-adaptation time-varying preset performance controller according to the error transformation model; thirdly, designing an altitude subsystem self-adaptation time-varying preset performance controller according to the error transformation model; fourthly, performing stabilizing analysis and performance analysis according to the speed subsystem self-adaptation time-varying preset performance controller and the altitude subsystem self-adaptation time-varying preset performance controller. The hypersonic aircraft self-adaptation time-varying preset performance control method has the advantages that the online approximation algorithm complexity of an unknown nonlinear power model is lowered while the saturation constraint conditions of an aircraft actuating mechanism are not violated; the self-adaptation high-precision control of a hypersonic aircraft is achieved while the stability of the control system of the aircraft is guaranteed.