1099 results about "Double loop" patented technology

The present invention relates to an apparatus and process for polymerizing olefins. One embodiment comprises polymerizing at least one monomer in a first loop reactor in the presence of a catalyst to produce a first polyolefin fraction. A portion of the first polyolefin fraction is transferred to a second loop reactor, connected in series with the first loop reactor. The process further comprises polymerizing in the second loop reactor at least one monomer in the presence of a catalyst to produce a second polyolefin fraction in addition to the first polyolefin fraction. The combination of the first and second polyolefin fractions can produce a polymer resin fluff having bimodal molecular weight distribution.

In a burst-mode, high-speed spread-spectrum communications system, faster convergence of a receiver's automatic gain control (AGC) circuit reduces the time required to bring a received signal within the operating range of an operation amplifier and other radio-frequency and digital sections of the receiving system. A gain control circuit includes a coarse-gain feedback loop and a fine-gain feedback loop to improve convergence speed and at the same time maintain the stability of the AGC circuit. The coarse-gain feedback loop quickly brings the received signal, using a large gain signal, to the desired operating range. The fine-gain feedback loop uses a smaller gain signal to gradually smooth the received signal to avoid saturation on the A/D converters.

A coding structure is configured to improve coding efficiency together with reduced encoding and decoding complexity for scalable video encoding. Especially, the case of coding multiple FGS layers on top of a discrete layer is considered. For coding multiple FGS layers, a decoder-oriented two-loop structure is used. At the decoder side, the new structure has similar complexity as the two-loop structure while providing similar coding performance as multi-loop structure. The coding structure and method is configured for preventing the drift effect in case of partial decoding due to the usage of FGS layer for inter-discrete-layer prediction, and aims at effectively utilizing temporal prediction in FGS layer coding to improve coding efficiency. The coding method can avoid additional transform operations; avoid applying in-loop de-blocking filter to FGS layers; and use simpler residual transform on FGS layers.

The present invention discloses a high-voltage double-loop safety system of electric vehicle and a method thereof. The high-voltage double-loop safety system of electric vehicle comprises a hardwired control loop which is composed of a VMS vehicle controller, a motor controller assembly, a driving motor and a high-voltage power battery pack assembly through hardwired connection in series, a VMS vehicle controller which is connected in parallel in the vehicle CAN network, and a communication network control loop composed of an MCU control plate in the motor controller assembly and a BMS battery management system in the high-voltage power battery pack assembly. The control method of the invention mainly determines whether the power battery outputs high-voltage electricity through the self testing of each control system and the safety information interaction checking of CAN communication network. The high-voltage double-loop safety system of electric vehicle according to the invention can reliably realize the purpose of protection of electric vehicle or the high-voltage electric device and high-voltage power transmission line in a hybrid power vehicle and the operator safety. The safety and reliability of high-voltage electricity can be greatly increased.

Among networks of ring configuration, the dual ring topology with source steering or wrapping capabilities offers numerous advantages over a single ring topology. In the management of a ring network, problems consist in making sure that every node in the ring is aware of the current ring topology. If, however, two or more links fail even in a dual ring network, the propagation of discovery packets is not guaranteed. A new topology discovery technique is disclosed. In accordance with one aspect of the invention, the algorithm uses only one discovery packet format and a set of timers for a variety of actions to be performed at each node on the ring. The protocol finds valuable applications in RPR and many similar network architectures.

A double-motor driving type electronic hydraulic brake system capable of actively simulating pedal feeling comprises a brake pedal, a fluid storage tank used for storing brake fluid, a pedal displacement sensor, a pedal force sensor, a hydraulic force sensor, an electronic control unit, an electromagnetic valve, an electronic stability control module, a brake master cylinder and a secondary master cylinder. An electric control linear movement module comprises a rotating motor and a speed reduction and moment increasing mechanism which converts the rotating movement of the motor into linear movement to achieve the active control over system hydraulic brake force and pedal force. The pedal force of a driver can be fully used for reducing pressure. While the active control over the pedal force is achieved, a pedal force simulator of a complex structure is omitted, the feeling of a brake pedal is guaranteed, and the accurate automobile brake condition is fed back to the driver. The active control over the hydraulic force is achieved, and the brake requirement for automatic driving vehicles is met; maximum braking energy recovery is achieved, control is precise, and the response speed is high; double-loop braking is achieved, failure protection is considered thoroughly, and the safety is good.

A liquid crystal composition is provided that satisfies at least one characteristic among the characteristics such as a high maximum temperature of a nematic phase, a low minimum temperature of a nematic phase, a small viscosity, a large optical anisotropy, a large dielectric anisotropy, a large specific resistance, a high stability to ultraviolet light and a high stability to heat, or is properly balanced regarding at least two characteristics. An AM device is provided that has a short response time, a large voltage holding ratio, a large contrast ratio, a long service life and so forth. The liquid crystal composition contains a specific tricyclic compound having a large optical anisotropy as the first component and a specific tetracyclic compound having a large dielectric anisotropy as the second component, and may contain a specific bicyclic compound having a particularly small viscosity as the third component. The liquid crystal composition has a nematic phase. The liquid crystal display device contains the liquid crystal composition.

The invention relates to a welding device, in particular to a circular and longitudinal seam welder special for automatically welding multi-specification tank bodies. The speed-variable circular and longitudinal seam welder applied to the multi-specification tank bodies mainly comprises four parts, namely a bed body (1), a headstock (2), a beam mechanism (12) and a tailstock (5). Compared with the prior art, the circular and longitudinal seam welder has the advantages of adapting to the change of the tank body diameter range of phi300 to 1,400mm and welding linear speed range of 200 to 1,200mm/min, realizing edge sealing and dual circular and longitudinal seam welding of the tank bodies, along with multiple functions, compact structure, convenient operation, high stability and low production cost.

The invention relates to a position/force hybrid control method for a space manipulator, which is a double-loop control method combining a Cartesian space and a joint space. Compared with a conventional control method on the basis of an integral model, which has the problems of oscillation of the transition process and algorithm complexity, the position/force hybrid control method for the space manipulator has the advantages that the position/force hybrid control problem is decomposed into the planning problem of the Cartesian space and the control problem of the joint space; a position/force kinematic plan from the Cartesian space to the joint space and kinematic control of the joint space are given out; an internal and external loop control system is formed; and position control on a free space at the tail end of the manipulator and contact force control in a space restrained by the environment are implemented. A simulation result for a SDOF ( Seven Degrees of Freedom) redundant manipulator proves that the method disclosed by the invention is simple to operate, is effective and is easy for engineering realization.

The invention relates to a precise tracking and measuring method of a high dynamic signal of an air fleet link, belonging to the technical field of aeronautical data links and radio navigation, and aiming at providing a precise tracking and measuring method of the high dynamic signal the an air fleet link and an implementation structure to solve the problems in the prior art. The invention provides a system framework of the precise tracking and measuring method of the high dynamic signal of the air fleet link, which can be implemented on a digital signal processor (DSP) and a FPGA (field programmable gate array) of a circuit board, and overcomes the defects of the unfavorable precision of a traditional high dynamic receiver by utilizing a double-loop structure of a frequency tracking loop of carrier tracking and a phase locking loop as well as a code phase locking loop to realize the high precise tracking under a high dynamic condition. The method can be widely applied to satellite navigation receivers, range measurement systems and communication systems based on a quiescent carrier modulation direct sequence spread spectrum system.

The invention discloses an efficient multi-mode DC-DC converter in a wide voltage conversion range. The multi-mode DC-DC converter comprises a Buck-Boost power conversion module, a driving module, a band gap reference module, an IC internal power supply module, a waveform generator module, a working mode selection module, a protection module, a voltage detection module, a current detection module, a soft starting module, a PWM controller module and an LDO controller module. The multi-mode DC-DC converter can realize total integration of a switching tube and a synchronous rectifying tube, and is externally connected with an inductor and an output filter capacitor; the input voltage range is 2.5 to 5.5 volts, the output voltage range of 2.5 to 5.5 volts is adjustable, the maximum output current is 1,000 milliamperes, the maximum working frequency is 1MHz, the precision of the output voltage is less than 5 percent, and a system enters an intermittent working mode during light load to realize the integral system efficiency of more than 80 percent; a control loop adopts double-loop control of voltage and current, realizes the control of a PWM mode and a PFM mode, and can realize LDO control in a specific voltage conversion range; and the over-temperature, over-voltage and over-current protection functions are realized.

A catheter(10) includes an elongated tubular member (14) having a proximal end (34) opposite a distal end (36). The distal end has a loop hole (70), at least one transition hole (72), and an end hole (78). A thread (60) has one end (62) fixed at the proximal end. The thread extends through the interior of the tubular member and out from the loop hole. The thread then extends through the transition hole and re-enters the tubular member at the end hole (78). The thread has a pulling end (64) exiting the tubular member at the proximal end. Application of a pulling force on the pulling end causes the distal end to form a first loop from the loop hole to the transition hole and a second loop from the transition hole to the end hole. The tubular member has a plurality of drainage/infusion ports (40) between the distal end and the end hole. The ports are in a radial position substantially opposite the radial position of the loop hole. The catheter (10) further includes a hub (12) having a channel (20) therethrough. The hub is coupled to the tubular member and a pivotable locking member (24) is coupled to the hub. The locking member secures the thread to the hub after the thread is fully pulled. The number of loops formed can be increased by adding more transition holes.

The invention relates to a knitted fabric with multiple functions of keeping warm, absorbing moisture, releasing sweat and resisting bacteria. The knitted fabric comprises an outer layer, a middle layer and an inner layer, wherein the outer layer and the inner layer are connected with the middle layer through double-sided knitted structures; the outer layer has double-loop structure formed by interweaving hydrophilic yarns and elastic yarns; the inner layer has double-loop structure formed by interweaving moisture-transfer functional yarns containing antibacterial substances and elastic yarns; and the middle layer is made of elastic yarns with moisture-transfer function. A weaving method for the fabric comprises the following steps of: arranging a dial needle and a cylinder needle on a double-sided circular weft knitting machine in a double-rib arrangement mode; weaving the outer layer of the fabric by loops on the dial needle in a plaiting mode; weaving the inner layer of the fabric by loops on the cylinder needle in a plaiting mode; and finally weaving the middle layer of the fabric, and connecting the middle layer, the inner layer and the outer layer. The fabric has multiple functions of keeping warm, absorbing moisture, releasing sweat and resisting bacteria, has integral elasticity, and has the characteristics of flat appearance, massiveness, soft handfeel and the like.

Disclosed are methods and apparatuses for cooling a work piece surface using a dual-loop cooling system. The system includes a vapor-compression loop and a liquid-evaporation loop. The loops are configured to prepare a coolant at or approximately at saturation for delivery into a chamber for cooling the surface. A preferred liquid-evaporation loop includes a chamber, a phase separator, a liquid pressurizer, and a vapor mixer that heats the coolant to or near its saturation temperature. A preferred vapor-compression loop includes the phase separator, a compressor, a condenser, an expansion valve, and a return line. The vapor mixer preferably heats the coolant by mixing liquid coolant with vapor coolant derived from the vapor-compression loop. A two-phase flow detector may be disposed downstream of the vapor mixer and be in communication with a vapor valve disposed upstream of the vapor mixer to ensure that an appropriate amount of vapor is fed into the vapor mixer to induce evaporation. Methods include cooling a surface by cycling a coolant through the liquid-evaporation loop and preparing the coolant at saturation with vapor derived from the vapor-compression loop.

An instrument (10) is provided having a shaft (12) extending to a distal end (16). The distal end (16) has a distal tip member (40) having a cavity (42, 83), and a passageway (44, 80) extending to the cavity through which a first suture end (48A) of a loop of suture (48) extends from a tissue site to facilitate a user looping a second suture end (48B) around the first suture end (48A) between the distal tip member (40) and the tissue site to form a knot (48C). Advancing of the distal tip member (40) while drawing the first suture end (48A) through the passageway (44, 80) pushes the knot (48C) for placement at the tissue site. The distal tip member (79) of another embodiment provides an additional open-sided passageway (81) through which the second suture end (48B) is passed to assist in forming and pushing a knot at to the tissue site. A more secure knot (50) may be formed by a double loop (49A) and then a single loop (49B) by the second suture end (48B) around the first suture end (48A) and appropriate tensioning of the first and second suture ends when the knot is pushed to the tissue site. The distal end (16) further has two openings (46, 47) through which the two suture ends (48A, 4813) are passed from the placed knot (48C, 50), and a blade (38) in the distal end (16) is positionable to cut the two suture ends near the tissue site to trim the suture away from such knot.

A radio frequency (RF) receiver device comprises a receiver system that receives an analog radio frequency signal and downconverts the analog radio frequency signal to a downconverted analog signal, the receiver system further including a peak signal detector configured to determine a peak signal level of the downconverted analog signal, and an automatic gain control adjustment element configured to determine whether the peak signal level falls within a predetermined range, and configured to generate, in the RF receiver, a gain control signal controlling the gain of at least one analog component based on whether the peak signal level falls within the predetermined range.

An double loop exercise strap that includes both an outer strap anchored to a fixed object (e.g., a wall, rail or other fixed platform) and an inner strap that wraps firmly around a limb, extremity (e.g., hand or foot) or torso of the human body. The inner strap has two ends, a fixed end that may advantageously be sewn or attached to the outer strap and a free end that wraps around the human limb, extremity or torso and is threaded through an outer strap slot before being attached to the outside of the outer strap using VELCRO™, buckles or other types of fasteners to thereby create a closed double loop system

The invention relates to double loop double pyrolysis incinerator and its using method. Its features are that drying apparatus is formed by horizontal rotary kiln drying device, steam separator, and fume reflux line; the feed port of the horizontal rotary kiln is connected with discharge port of the feeding device; its discharge port is connected with the feed port above secondary burning chamber. While running, part of high temperature fume of secondary burning chamber can enter the rotary kiln to process reverse drying preheat and pyrolysis for the garbage; cooled fume is inducted into the secondary burning chamber by secondary fan after dehydrating by steam separator. Compared with exiting technique, the invention has the advantages of continual heat transfer, fast gasification rate, full burning, processing domestic garbage without auxiliary fuel etc.

The invention discloses a method in a boat control field and especially relates to the sliding mode-reverse step double loop trace tracking control method of an underactuated unmanned surface vehicle.The method comprises the following steps of firstly, establishing a three-degree-of-freedom motion mathematical model of the heading, the surging and the swaying of the unmanned surface vehicle; then, through an integrated pose sensor, measuring the current position information of the unmanned surface vehicle, combining the real-time position and the reference trace of the unmanned surface vehicle, calculating an error under a boat body coordinate system; and then, designing a kinematic loop trace tracking controller based on a backstepping method, and designing a dynamic loop trace trackingcontroller based on a sliding mode control algorithm. Through a sliding mode-reverse step double loop trace tracking controller, the trace tracking control of the unmanned surface vehicle Is realized,the unmanned surface vehicle can track a linear trace, and the stability and accuracy of unmanned surface vehicle navigation can be increased.

The invention discloses a control method of a four-axis unmanned aerial vehicle. The method includes the following steps that: S1, the attitude data of an attitude sensor in the four-axis unmanned aerial vehicle are acquired, and filtering and fusion are carried out on the attitude data, so that current attitude information can be obtained, wherein the attitude data include a current attitude angle and an angular velocity corresponding to the attitude angle; and S2, the four-axis unmanned aerial vehicle is controlled through a cascade double-loop PID control method, a deviation value between the current attitude information and target attitude information is adopted as the input quantity of an angle PID controller, the difference value of the current angular velocity and the output quantity of the angle PID controller is inputted into an angular velocity PID controller, and the output of the angular velocity PID controller is used for controlling a motor until the four-axis unmanned aerial vehicle achieves a target attitude. With the control method of the invention adopted, more accurate measurement data can be obtained, the accuracy of attitude data can be improved; the cascade double-loop PID control is adopted, so that the anti-interference performance of a system is enhanced; and therefore, the four-axis unmanned aerial vehicle has higher adaptability.

A switched mode voltage regulator has a digital control system that includes dual digital control loops. The voltage regulator comprises at least one power switch adapted to convey power between respective input and output terminals of the voltage regulator and a digital controller adapted to control operation of the power switches responsive to an output of the voltage regulator. The digital controller further comprises dual digital control loops in which a first control loop provides high speed with lower regulation accuracy and a second control loop has high accuracy with lower speed. Thus, the digital control system provides the advantages of both high speed and high regulation accuracy.

The invention relates to double-circular-seam automatic welding equipment, and belongs to the field of machines. Existing equipment can only weld a single circular seam at one time, and efficiency is low. The double-circular-seam automatic welding equipment comprises a welding gun and a machine frame, wherein the machine frame is provided with a main power pump, a speed changer, a linear guide rail, a straight guide rail driver, a three-jaw chuck and a clamping device, wherein the three-jaw chuck and the clamping device are used for clamping workpieces, the three-jaw chuck is installed on the speed changer, the linear guide rail driver is installed on the linear guide rail, the linear guide rail is provided with a rectangular plate, the rectangular plate and the linear guide rail are arranged in the same direction, one face of the rectangular plate is movably connected with the linear guide rail, the other face of the rectangular plate is vertically provided with two lifting cylinders, a piston rod of each lifting cylinder is provided with a welding gun regulating device, and each welding gun regulating device is provided with a fixing plate. By the adoption of the structure, welding can be carried out on two circular seams at the same time, not only is efficiency improved, but also the arrangement is more compact and reasonable, the double-circular-seam automatic welding equipment can be suitable for welding workpieces of various structures, and components of the equipment are also easy to obtain.

The invention relates to a converging type solar thermal power device capable of condensing sunlight, storing heat using high temperature phase change energy storage material and driving double loops, belonging to the technical field of solar energy collection and solar energy heat utilization. The device comprises a funnel-shaped converging type solar energy condenser, a transparent light transmitting window, an energy accumulator, a high temperature heat-conducting oil heat supply circulating system, a superheated steam generator, and a Rankine cycle-based heat-power converting system. The sunlight is condensed by the funnel-shaped converging type solar energy condenser, and entered into the energy accumulator through the transparent light transmitting window to realize high temperature storage therein, the high temperature heat-conducting oil heat supply circulating system transmits the high temperature in the energy accumulator to the superheated steam generator to heat working fluid to generate high pressure high temperature superheated steam therein, and converts heat energy to power through thermodynamic cycle. The invention is a device for supplying power or electric energy for user by condensing sunlight, storing heat using high temperature phase change energy storage material, and driving heat-power converting system using high temperature heat energy.