Abstract: A light adjustment circuit for alternating-current light emitting diodes (AC-LED's) connected to an AC power supply and a plurality of AC-LED's comprises: a light adjustment unit, being capable of modulating AC power from the AC power supply while providing the plurality of AC-LED's with the modulated AC power; and a pulse width modulation (PWM) control circuit, being capable of modulating an external voltage signal in correspondence to variation in input AC power to enable each of the AC-LED's to achieve a predetermined brightness; wherein the AC-LED's are turned off by modulating the external voltage signal to prevent the AC-LED's from being burnt out when the input AC power is too high.

Abstract: A light adjustment circuit for alternating-current light emitting diodes (AC-LED's) connected to an AC power supply and a plurality of AC-LED's comprises: a light adjustment unit, being capable of modulating AC power from the AC power supply while providing the plurality of AC-LED's with the modulated AC power; and a pulse width modulation (PWM) control circuit, being capable of modulating an external voltage signal in correspondence to variation in input AC power to enable each of the AC-LED's to achieve a predetermined brightness; wherein the AC-LED's are turned off by modulating the external voltage signal to prevent the AC-LED's from being burnt out when the input AC power is too high.

Abstract: An enhanced heat transfer device with electrodes is provided, which is applied to a heat exchanger with a plurality of fluid channels and includes a plurality of electrodes mounted in the fluid channels of the heat exchanger; a plurality of sensor units mounted in the fluid channels of the heat exchanger for measuring mass flow rates of fluids in the fluid channels; and a power source for providing voltage to the electrodes. The power source is used to drive the electrodes to produce turbulence to fluids passing through the fluid channels according to measured mass flow rates from the sensor units, so as to facilitate uniform fluid flows in the plurality of fluid channels and reduce effect of thermal boundary layer in the fluid channels to thereby enhance heat transfer performance for the heat exchanger.

Abstract: A PDMS valve-less micro pump structure includes a PDMS body having a contour surface, a membrane covering the contour surface of the PDMS body, and a PZT actuator located on the membrane. The contour surface of the PDMS body to be sealed by the membrane and the PZT actuator has in series a lead-in cavity, a lead-in nozzle structure, a main cavity, a lead-out nozzle structure, and a lead-out cavity. The PZT actuator is located right above the main cavity. By providing the PDMS as a material to form the body of the micro pump, the micro pump can then be mass-produced with less cost and simpler structuring. Also, substantial elasticity and bio-compatibility for the micro pump can be achieved.

Abstract: A magnetocaloric refrigeration device, placed in a controllable magnetic field, includes a heat release/absorption module. The heat release/absorption module includes a magnetocaloric working unit and at least one heat pipe. The magnetocaloric working unit is made of a magnetocaloric material. The temperature of the unit changes as the magnetic field is applied or removed. The heat pipe includes evaporation and condensation portions respectively extending from top and bottom of the magnetocaloric working unit. When a magnetic field is applied to the magnetocaloric working unit to absorb heat, the lower condensation portion of the heat pipe transfers heat upward to the magnetocaloric working unit. When the magnetic field is removed from the magnetocaloric working unit to release heat, the heat from the magnetocaloric working unit is transferred to the outside through the upper heat release portion. The magnetocaloric refrigeration device has advantages of simple structure, low production cost, and small size.

Abstract: An enhanced heat transfer device with electrodes is provided, which is applied to a heat exchanger with a plurality of fluid channels and includes a plurality of electrodes mounted in the fluid channels of the heat exchanger; a plurality of sensor units mounted in the fluid channels of the heat exchanger for measuring mass flow rates of fluids in the fluid channels; and a power source for providing voltage to the electrodes. The power source is used to drive the electrodes to produce turbulence to fluids passing through the fluid channels according to measured mass flow rates from the sensor units, so as to facilitate uniform fluid flows in the plurality of fluid channels and reduce effect of thermal boundary layer in the fluid channels to thereby enhance heat transfer performance for the heat exchanger.