Abstract: A method of orthopedic treatment includes steps of: by using a computer aided design (CAD) tool based on profile data that is related to a to-be-treated part of a bone of a patient, obtaining a model of a preliminary instrument that substantially fits the to-be-treated part; by using the CAD tool, obtaining a model of a patient specific instrument (PSI) based on the model of the preliminary instrument; producing the PSI based on the model of the PSI, the PSI being adjustable; performing medical operation on the to-be-treated part, and then attaching the PSI to the to-be-treated part; after attaching the PSI to the to-be-treated part, adjusting the PSI such that the PSI is adapted to real conditions of the to-be-treated part.

Abstract: A driving circuit for light-emitting diodes includes a power unit providing an input voltage, a voltage regulation unit providing a voltage-increasing loop and a voltage-decreasing loop and having an energy-storing capacitor with an intermediate voltage therebetween, a current control unit generating a driving current for the light-emitting diodes according to the intermediate voltage, and a switching control unit. The switching control unit generates a reference voltage based on the input voltage and compares the reference voltage with a feedback voltage associated with driving current. The switching control unit controls the voltage regulation unit to increase the intermediate voltage through the voltage-increasing loop when the feedback voltage is smaller than the reference voltage. The switching control unit controls the voltage regulation unit to decrease the intermediate voltage through the voltage-decreasing loop when the feedback voltage is larger than the reference voltage.

Abstract: A latex leather sheet fabrication method includes the steps of (a) pre-heating natural latex to about 30.degree. C.; (b) flow mixing pre-heated natural latex with a chemical solution containing oleic acid, sulfur and zinc oxide powder by flow mixing for about 1.about.3 hours; (c) mixing the latex mixture with forced air into a foamed viscous liquid; (d) shape-forming the foamed viscous liquid into a hardened foamed sheet material; (e) heating and drying the foamed sheet material into a foamed leather sheet; and (f) air cooling the finished latex leather sheet.