Abstract: A feedback control numerical machine tool and a method thereof are provided. The machine tool includes at least two spindles, an acoustic frequency detecting module, at least two spindle position detecting modules, and a control module. The spindles machine a workpiece. The acoustic frequency detecting module detects an acoustic frequency of the spindles when machining the workpiece. The spindle position detecting modules detects position information of the spindles when machining the workpiece. The control module acquires the acoustic frequency and the position information of the spindles, monitors whether any of the spindles chatters according to the acoustic frequency of the spindles, and performs chattering avoidance to the spindle that chatters according to the position information of the spindles. As such, the present disclosure performs chattering monitoring to a plurality of spindles and avoids the chattering immediately.

Abstract: A chatter avoidance method and device is provided, including steps of: providing a stable operating condition plot; partially removing a first layer of a workpiece with a predetermined first removal depth according to a safe removal depth of the stable operating condition plot and sensing a chatter caused by the removal operation; if no chatter is sensed, completing the removal operation, otherwise, continuing to partially remove the first layer with a second removal depth less than the predetermined first removal depth; and determining a minimum removal depth according to the removal operation, and removing a last layer of the workpiece with a last removal depth less than or equal to the minimum removal depth, allowing the workpiece to have a target thickness. The disclosure prevents a chatter from continuously occurring without requiring a shut-down and thereby maintains a desired production rate.

Abstract: A method and an apparatus for generating contact relationship data in a network communication system are disclosed. The method includes: selecting target users from contacts of an introducer according to a selecting instruction; sending an introducing request to each of user accounts of the target users; monitoring response instructions from the user accounts of the target users, and generating contact relationship data between the user accounts of the target users after detecting that all the user accounts of the target users return response instructions for accepting the introducing request. The apparatus comprises: a target user selecting module, a request sending module, a response monitoring module, and a contact relationship data generating module. Using the present invention, the convenience and success rate of generating contact relationship data is improved.

Abstract: A support device includes a supporting main body, a first angle rotation unit, a second angle rotation unit, a height adjustment structure, an absorbing unit and a driver motor unit. The absorbing unit is pivotally connected to the first angle rotation unit. The driver motor unit includes a first driving element, a second driving element and a third driving element. The first driving element drives the first angle rotation unit to adjust a rotation angle of the absorbing unit. The second driving element drives the second angle rotation unit for enabling the supporting main body to rotate around an axial thereof. The third driving element drives the height adjustment structure for enabling the supporting main body to move along the axial thereof. In addition, an support unit system and a support unit control system are also provided.

Abstract: Provided are systems and methods to generate single-cycle THz pulses from a few tens of nanometers thin layer of split ring resonators (SRRs) via optical rectification of femtosecond laser pulses. The emitted THz radiation, with a spectrum ranging from about 0.1 to 4 THz, arises exclusively from pumping the magnetic-dipole resonance of SRRs around 200 THz. This resonant enhancement, together with pump polarization dependence and power scaling of the THz emission, underpins the nonlinearity from optically induced circulating currents in SRRs, with a huge effective nonlinear susceptibility of 0.8×10?16 m2/V that far exceeds surface nonlinearities of both thin films and bulk organic/inorganic crystals and sheet nonlinearities of non-centrosymmetric materials such as ZnTe.

Abstract: An apparatus and method for transforming NC programs are provided, and the apparatus is electrically connected to a controller configured to, according to a NC program, command a machine to drive a cutting tool to cut a workpiece. The apparatus includes a triggering module, a coordinate position processing module, and a storage module. The triggering module is electrically connected to the controller. The coordinate position processing module is electrically connected to the controller and the triggering module. The storage module is electrically connected to the coordinate position processing module. The triggering module triggers the controller to execute the NC program in a single block mode. The coordinate position processing module is triggered by the triggering module to acquire at least one coordinate position from the controller. The storage module stores the at least one coordinate position. The triggering module simultaneously triggers the controller and the coordinate position processing module.

Abstract: A chatter avoidance method and device is provided, including steps of: providing a stable operating condition plot; partially removing a first layer of a workpiece with a predetermined first removal depth according to a safe removal depth of the stable operating condition plot and sensing a chatter caused by the removal operation; if no chatter is sensed, completing the removal operation, otherwise, continuing to partially remove the first layer with a second removal depth less than the predetermined first removal depth; and determining a minimum removal depth according to the removal operation, and removing a last layer of the workpiece with a last removal depth less than or equal to the minimum removal depth, allowing the workpiece to have a target thickness. The disclosure prevents a chatter from continuously occurring without requiring a shut-down and thereby maintains a desired production rate.

Abstract: The present disclosure provides a support device. The support device includes a supporting main body, a first angle rotation unit, a second angle rotation unit, a height adjustment unit, an absorbing unit and a driver motor unit. The absorbing unit is pivotally connected to the first angle rotation unit. The driver motor unit includes a first driving element, a second driving element and a third driving element. The first driving element drives the first angle rotation unit to adjust a rotation angle of the absorbing unit. The second driving element drives the second angle rotation unit for enabling the supporting main body to rotate around an axial thereof. The third driving element drives the height adjustment unit for enabling the supporting main body to move along the axial thereof. In addition, an support unit system and a support unit control system are also provided.

Abstract: A process-orientated design method for machine tool structures comprises the steps of: (A) Defining design conditions including initial configurations, cutting requirements and boundary conditions for the machine tool; (B) Calculating cutting ability to generate information realizing a relationship between a maximum cutting depth and a spindle speed of the machine tool based on the initial configurations and the cutting requirements; (C) Performing an optimization to generate a frequency range for optimization based on the information relating the maximum cutting depth and the spindle speed; (D) Performing structural topology optimization to generate an optimized model based on the frequency range for optimization, the initial configurations and boundary conditions; and (E) Determining whether the optimized model fits the constraint condition; if positive, ends the design steps, and otherwise repeats steps (B)˜(D) until an optimized model fits the constraint condition appears.

Abstract: Provided are systems and methods to generate single-cycle THz pulses from a few tens of nanometers thin layer of split ring resonators (SRRs) via optical rectification of femtosecond laser pulses. The emitted THz radiation, with a spectrum ranging from about 0.1 to 4 THz, arises exclusively from pumping the magnetic-dipole resonance of SRRs around 200 THz. This resonant enhancement, together with pump polarization dependence and power scaling of the THz emission, underpins the nonlinearity from optically induced circulating currents in SRRs, with a huge effective nonlinear susceptibility of 0.8×10?16 m2/V that far exceeds surface nonlinearities of both thin films and bulk organic/inorganic crystals and sheet nonlinearities of non-centrosymmetric materials such as ZnTe.

Abstract: A feedback control numerical machine tool and a method thereof are provided. The machine tool includes at least two spindles, an acoustic frequency detecting module, at least two spindle position detecting modules, and a control module. The spindles machine a workpiece. The acoustic frequency detecting module detects an acoustic frequency of the spindles when machining the workpiece. The spindle position detecting modules detects position information of the spindles when machining the workpiece. The control module acquires the acoustic frequency and the position information of the spindles, monitors whether any of the spindles chatters according to the acoustic frequency of the spindles, and performs chattering avoidance to the spindle that chatters according to the position information of the spindles. As such, the present disclosure performs chattering monitoring to a plurality of spindles and avoids the chattering immediately.

Abstract: A structural topology optimization design method is provided. A structural topology optimization question is defined to determine at least one set of load and restriction condition and a parameter of lower limit of volume capacity related to a design space model. This model is divided into mesh grids for performing finite element analysis (FEA). Strain energy of each element after FEA is obtained according to the established load and restriction condition and used as a basis for calculating sensitivity of each element. A part of elements is removed or retained according to the degree of sensitivity of each element, and the structural profile and the total volume capacity and total strain energy of residual elements of the structural profile are recorded after each loop was completed. A display interface is used to sequentially show the structural profile and a relationship diagram of structural volume capacity vs structural strain energy.

Abstract: A surveillance apparatus and an associated surveillance method are provided. The surveillance apparatus includes a video recorder, an infrared sensor and a motion detector. The surveillance method includes following steps. First, a video stream corresponding to a surveillance region is captured. Then, an infrared status of an infrared sensing region is sensed to selectively generate a trigger signal. The infrared sensing region and the surveillance region are partially overlapped. A motion detection signal according to the video stream is selectively generated. Whether a moving object is detected is determined according to the trigger signal and the motion detection signal.

Abstract: A constant current control circuit includes a current source output module and at least two output circuits. Each of the output circuits includes an automatic constant current regulating module, a power transistor drive and control module electrically coupled to automatic constant current regulating module, and a load module formed of one or more LED devices and electrically coupled to a power transistor drive and control module. The constant current control circuit in operation tracks changes in current of each output circuit and regulates the currents of all the output circuits accordingly.

Abstract: A machine tool design method includes: receiving a finite element model of tool-spindle system including a cutting tool, a working spindle speed range, and a target cutting depth; providing a simplified finite element model of main frames of machine tool and initializing its configuration parameters including an equivalent stiffness and an equivalent mass; combining the simplified finite element model of main frames of machine tool with the finite element model of tool-spindle system to construct an equivalent machine tool model; according to a response of the configuration parameters, proceeding a cutting stability prediction of the equivalent machine tool model, and computing an objective function value based on a predicted result; and determining whether the objective function value meets a preset design requirement, if yes, employing the configuration parameters to be references to design a machine tool, if not, updating the configuration parameters and proceeding the cutting stability prediction again.

Abstract: The invention provides a constant current control device and a television including the constant current control device. The constant current control device includes a constant current control module and a switched-mode power supply module used for providing a stable voltage for a load. The constant current control module includes a constant current source unit used for providing a reference current, a constant current control unit used for keeping a current flowing through the load constant as the reference current, and a feedback unit used for keeping the voltage of the constant current control unit constant. The present invention, with a simple circuit structure, implements the objective of precisely controlling a current passing through a load.

Abstract: A telescopic shaft assembly includes a seat, a shaft body disposed movably in the seat, and a plurality of slide blocks located between the shaft body and the seat. The shaft body has a convex portion and a recessed portion opposite to each other. One end of the convex portion far away from the recessed portion has a top surface. One of the plurality of slide block is disposed on the top surface. The recessed portion has two inner side wall surfaces opposite to each other and a bottom surface located between the two inner side wall surfaces. Each of the two inner side wall surfaces forms an obtuse angle with the bottom surface. Two of the rest of the plurality of slide blocks are disposed on the two inner side wall surfaces respectively.

Abstract: A hydrostatic rail guide includes a guide rail, a guide carriage, a hydrostatic supply device, a measurement device and a controller. The guide carriage is hydrostatically mounted on the guide rail and has a hydrostatic channel filled with oil. The oil keeps the guide carriage and the guide rail at a gap. The hydrostatic supply device is adapted for supplying the oil to the hydrostatic channel and adjusting the pressure of the oil. The measurement device is installed on the guide carriage and adapted for detecting the gap between the guide carriage and the guide rail and for producing a distance signal of the measured gap. The controller is connected to the hydrostatic supply device and the measurement device. The controller is adapted for controlling the hydrostatic supply device, based on the distance signal, in order to adjust the hydrostatic pressure of the oil after being pressurized.

Abstract: The invention provides a working trough and a method for maintaining a uniform temperature of a working fluid. The working trough is applied to an electrical discharge machine that performs wire cutting using the working fluid. The method for maintaining a uniform temperature of the working fluid is applied to the working trough and characterized by forming opening structures in a receiving slot of the working trough such that a spiral swirl having a predetermined height is allowed to be formed in the working fluid, thereby maintaining a uniform temperature of the working fluid in the receiving slot when a wire cutting process is performed in the working fluid by the electrical discharge machine. The disturbance of the spiral swirl also facilitates the discharge of scraps. The present invention further has an advantage of low cost.

Abstract: Electrospinning from a melt or solution by means of an electric field between a fibre source such as a spinneret or a bubble surface and a moving collector comprising a wire card of which the wires are electrically connected. The spinneret or melt or solution may be held at high potential and the wires earthed. The method produces an aligned nanofibre web that can be made into strands, yarns, cable or rope or non-woven fabrics such as stitch bonded and stitch knitted fabric.