Abstract: A parking information sensing device is disclosed. Each parking space in a parking lot is disposed with a parking information sensing device, detecting whether a car on the parking space. By means of a driving control circuit, the sensing device drives a light emitting unit to emit a light and a reflecting element of the parking space is on a pathway of the light. Light is reflected by the reflecting element and then passes light sensing unit that detects the reflected light and generates a first sensing signal sent to the driving control circuit. Thus the driving control circuit judges if there is no vehicle on the parking space. On the other hand, it judges if there is a car on the parking space according to another sensing signal. The sensing device further includes a first transmitting/receiving unit that forms a wireless mesh network among parking information sensing devices.

Abstract: A method for producing 1,4-bis(dichloromethyl)tetrafluorobenzene is disclosed, which is achieved by reacting tetrafluoroterephthaldehyde, SOCl2 and organic solvents. In the synthesis of 1,4-bis(dichloromethyl)-tetrafluorobenzene by adding formamides as catalyst, there are remarkable advantages which include shortening the reaction time; simplifying the synthesizing steps and raising the yield of the product.

Abstract: An aerial vehicle speed correlation method for two-dimensional visual reproduction of laser radar images of the present invention is capable of altering and controlling the output timing of the invention's laser radar system rated output lines based on the moving distance and the speed of an aerial vehicle. The speed error correlation method of the present invention is not limited to outputting one output line for every scanned line (N) for reducing the accumulation of geometric distortion error along the in-track direction of the scan frame. The speed correlation method of the present invention uses a set of generated fire table of equation to correct tangential error along the cross-track direction and to improve the reproduction quality of the laser radar images.

Abstract: An apparatus and method for demodulating a square root of the sum of squares of two inputs I and Q in a digital signal processing are provided. The square root {square root over (I2+Q2)} is approximated by an equation aX +bY, wherein coefficients a and b are special binary numbers. Due to the numbers, the square root {square root over (I2+Q2)} can be quickly computed by the operation of shifting and addition. A plurality of possible approximation values for the coefficients a and b are provided, as well as the use of a comparator to select the maximal one among the possible approximation values.

Abstract: An envelope detection method by using a peel cone approximation concept and an envelope detection circuit which implements the envelope detection method are disclosed. The envelope detection circuit includes an absolute value-determining circuit, a maximum/minimum value-determining circuit, a plurality sets of comparison circuits, an address encoder, a read only memory (ROM), and a multiplier/adder. A delaying circuit for synchronization is further included in the envelope detection circuit. With the method and the circuit for an envelope detection by using a peel cone approximation, advantages of a compact circuit structure, less operation latency, a low approximation error and a low cost are all achieved.

Abstract: A PWM controlling circuit includes a signal generator and two PWM controllers. The signal generator comprises an oscillator, a plurality of inverters, and two RC delay networks. The oscillator and the inverters are composed of elementary elements, respectively, such as diodes, resistors, inverters and capacitors. The PWM controlling circuit in accordance with the present invention can be implemented with low cost, and the duty cycles thereof are not limited to 50%.

Abstract: An interleaved current-fed forward converter apparatus includes two transformers each including two primary windings and a secondary winding connected to a load, two power switches each of which is connected between the primary windings of a corresponding one of the two transformers. The two power switches are alternately turned on and off in response to two pulse signals provided by a conventional controller. Two capacitors each are connected between the primary windings of respective one of the two transformers. One of the two transformers functions to transfer power to the load while the other functions as an inductor so as to alleviate the necessity of a conventional output inductor, and vice versa alternately. The two capacitors are alternately charged/discharged in response to the switching operation of the two power switches.

Abstract: A built-in input filter forward converter performs to shape an input current to a non-pulsating fashion. Shaping action is obtained by placing two cross-coupled capacitors to a plurality of splitting windings of a power transformer such that the input current will not be interrupted. The cross-coupled capacitors also operate as a lossless snubber by allowing the leakage inductance energy to be stored and recovered during normal operation. Thus significant improvements of reducing harmonic of the input current, input current ripple, and increasing the converter's efficiency are achieved.