Abstract: A polycarbonate resin composition of the present invention comprises about 40 to about 99% by weight of a polycarbonate resin (A), about 1 to about 60% by weight of an acrylic copolymer (B) having a high refractive index and a flexible structure, and about 0 to about 60% by weight of acrylic resin (C). A polycarbonate resin composition of the present invention can have excellent transparency and scratch resistance without requiring extra compatibilizers by including an acrylic copolymer having a high refractive index and a flexible structure with the polycarbonate resin.

Abstract: The present invention provides a transparent thermoplastic resin composition which may comprise (A) about 1 to about 100 parts by weight of an ultra-high molecular weight branched acrylic copolymer resin; (B) about 0 to about 99 parts by weight of an acrylic resin; and (C) about 0 to about 40 parts by weight of an acrylic impact modifier, based on 100 parts by weight of (A) and (B). The ultra-high molecular branched acrylic copolymer resin (A) may be prepared by polymerizing a monomer mixture comprising (a1) about 50 to about 99.899% by weight of a mono-functional monomer, (a2) about 0.1 to about 40% by weight of a (meth)acrylic monomer having a flexible segment represented following Chemical Formula 1, and (a3) about 0.001 to about 10% by weight of a branch-inducing monomer. The thermoplastic resin composition of the present invention can have improved transparency, scratch resistance, flowability, and impact strength.

Abstract: The present invention relates to an LED light emitting device and a driving method, and discloses a technology that may improve a slew rate of a channel current flowing through an LED channel when driving with a pulse width modulation method. For this, the present invention includes an LED channel consisting of a plurality of LED elements that are consecutively and serially connected, a current control switch that is connected to the end of the LED channel and performs a switching operation, and an operational amplifier that controls the switching operation of the current control switch according to a pulse width modulation signal. The LED driver samples an output voltage at the operational amplifier when the pulse width modulation signal is in an on state, and maintains the output voltage of the operational amplifier when the pulse width modulation signal is in an off state.

Abstract: A method of measuring methanol vapor concentration on a real-time basis and a methanol vapor concentration measuring apparatus used in fuel cells. The method of measuring methanol vapor concentration involves using an absorption spectrometry technique, that is, after measuring intensities I0 and I1 of light of a laser before and after passing through a space filled with methanol vapor and into which light is irradiated, the methanol vapor concentration is calculated by substituting the intensities I0 and I1 into an equation defined as I1/I0=exp (K·L·C), where K represents the absorption coefficient, L represents the length of the space through which the laser passes, and C represents the methanol vapor concentration.

Abstract: A load driver includes an inverter and an inverter driver. The inverter converts an input voltage into a driving voltage of a discharge lamp using at least one first switch for switching according to a duty ratio, and the inverter driver controls the inverter. The inverter driver controls the duty ratio using a voltage of a capacitor and a control signal having a waveform that is repeated with a predetermined frequency. The capacitor is charged and discharged by a current corresponding to a difference between a feedback voltage corresponding to a current flow to the discharge lamp and a reference voltage. Such inverter driver controls to gradually increase the output voltage of the inverter in the soft start period by setting the voltage of the capacitor as a voltage corresponding to the control signal.

Abstract: Disclosed is an aromatic vinyl-based thermoplastic resin composition. The thermoplastic resin composition is based on a thermoplastic resin including a rubber-modified acrylic graft copolymer and uses a branched aromatic vinyl copolymer resin including a silicon compound. The thermoplastic resin composition can exhibit both improved impact resistance and flowability. In addition, the thermoplastic resin composition can have excellent weather resistance and moldability.

Abstract: The present invention provides a phosphoric and acrylic copolymer resin that can have good transparency, scratch resistance and flame retardancy and a composition including the same. The phosphoric and acrylic copolymer resin includes repeat units of (A-1) at least one vinyl monomer and (A-2) at least one phosphoric monomer.

Abstract: The present invention provides a transparent thermoplastic resin composition which may comprise (A) about 1 to about 100 parts by weight of an ultra-high molecular weight branched acrylic copolymer resin; (B) about 0 to about 99 parts by weight of an acrylic resin; and (C) about 0 to about 40 parts by weight of an acrylic impact modifier, based on 100 parts by weight of (A) and (B). The ultra-high molecular branched acrylic copolymer resin (A) may be prepared by polymerizing a monomer mixture comprising (a1) about 50 to about 99.899% by weight of a mono-functional monomer, (a2) about 0.1 to about 40% by weight of a (meth)acrylic monomer having a flexible segment represented following Chemical Formula 1, and (a3) about 0.001 to about 10% by weight of a branch-inducing monomer. The thermoplastic resin composition of the present invention can have improved transparency, scratch resistance, flowability, and impact strength.

Abstract: A polycarbonate resin composition according to the present invention comprises a polycarbonate resin and an ultra-high molecular weight branched acrylic copolymer resin and can have excellent transparency, appearance, and flowability, as well as scratch resistance and impact strength.

Abstract: The present invention provides an aromatic vinyl thermoplastic resin composition including (A) about 10 to about 99% by weight of a thermoplastic resin (A) including (a1) an aromatic vinyl copolymer resin, (a2) a rubber-modified vinyl graft copolymer, or a combination of (a1) and (a2); and (B) about 1 to about 90% by weight of a branched aromatic vinyl copolymer resin including a silicon based compound. The thermoplastic resin composition of the present invention can have excellent impact strength, improved flow properties, and compactability.

Abstract: The present invention provides a control circuit for LED driver. A voltage-feedback circuit is coupled to LEDs to sense a voltage-feedback signal for generating a voltage loop signal. Current sources are coupled to the LEDs to control LED currents. A detection circuit is connected to sense voltages of current sources for generating a current-source loop signal in response to a minimum voltage of the current sources. Furthermore, a buffer circuit generates a feedback signal in accordance with the voltage loop signal and the current-source loop signal. The feedback signal is coupled to limit a maximum voltage of the LEDs and regulate the minimum voltage across the current sources.

Abstract: A polycarbonate resin composition of the present invention comprises about 40 to about 99% by weight of a polycarbonate resin (A), about 1 to about 60% by weight of an acrylic copolymer (B) having a high refractive index and a flexible structure, and about 0 to about 60% by weight of acrylic resin (C). A polycarbonate resin composition of the present invention can have excellent transparency and scratch resistance without requiring extra compatibilizers by including an acrylic copolymer having a high refractive index and a flexible structure with the polycarbonate resin.

Abstract: A polycarbonate resin composition can have improved transparency and scratch resistance of the present invention and comprises about 10 to about 99% by weight of polycarbonate resin (A); and about 1 to about 90% by weight of acrylic copolymer with ultra-low molecular weight and high refractive index (B). The resin composition of the present invention can further comprise acrylic resin (C). The acrylic copolymer with ultra-low molecular weight and high refractive index (B) can have a refractive index of about 1.495 to about 1.590 and a weight average molecular weight of about 3,000 to about 40,000 g/mol.

Abstract: A load driver includes an inverter and an inverter driver. The inverter converts an input voltage into a driving voltage of a discharge lamp using at least one first switch for switching according to a duty ratio, and the inverter driver controls the inverter. The inverter driver controls the duty ratio using a voltage of a capacitor and a control signal having a waveform that is repeated with a predetermined frequency. The capacitor is charged and discharged by a current corresponding to a difference between a feedback voltage corresponding to a current flow to the discharge lamp and a reference voltage. Such inverter driver controls to gradually increase the output voltage of the inverter in the soft start period by setting the voltage of the capacitor as a voltage corresponding to the control signal.

Abstract: A method of measuring methanol vapor concentration on a real-time basis and a methanol vapor concentration measuring apparatus used in fuel cells. The method of measuring methanol vapor concentration involves using an absorption spectrometry technique, that is, after measuring intensities I0 and I1 of light of a laser before and after passing through a space filled with methanol vapor and into which light is irradiated, the methanol vapor concentration is calculated by substituting the intensities I0 and I1 into an equation defined as I1/I0=exp (K·L·C), where K represents the absorption coefficient, L represents the length of the space through which the laser passes, and C represents the methanol vapor concentration.