Abstract: A semiconductor memory device can generate an under_drive voltage that maintains a predetermined level stably even in case of a change in the operation mode of the semiconductor memory device or the level of an external power supply voltage. The semiconductor memory device, which includes an external power supply voltage detector configured to detect a level of an external power supply voltage to generate the external voltage detection signal, an under_drive voltage detector configured to detect a voltage level of an under_drive voltage to generate the under_drive voltage detection signal, and an under_drive voltage generator configured to generate the under_drive voltage in response to the under_drive voltage detection signal with a variable driving force in response to the external voltage detection signal.

Abstract: An internal voltage generating circuit includes a first detector that compares an internal voltage and a first reference voltage to output a first detection signal. A second detector compares a supply voltage and a second reference voltage to output a second detection signal. A loop selection oscillator performs an oscillation operation in response to the first detection signal, selects a first loop or a second loop for performing the oscillation operation in response to the second detection signal, and outputs an oscillation signal. A charge pump performs a pumping operation according to the output of the loop selection oscillator and generates the internal voltage.

Abstract: A device for generating a pumping voltage and preventing an excessive increase in the pumping voltage includes a pumping voltage output unit that outputs a pumping voltage and adjusts the level of the pumping voltage in order to maintain a target voltage. The level of the pumping voltage is adjusted in response to a change in the level of the pumping unit. A release unit is included to detect an excessive pumping voltage. The release unit adjusts the level of the pumping voltage when the pumping voltage reaches a predetermined excessive level by compulsively decreasing the pumping voltage to prevent damage in the DRAM.

Abstract: A semiconductor memory device can generate an under_drive voltage that maintains a predetermined level stably even in case of a change in the operation mode of the semiconductor memory device or the level of an external power supply voltage. The semiconductor memory device, which includes an external power supply voltage detector configured to detect a level of an external power supply voltage to generate the external voltage detection signal, an under_drive voltage detector configured to detect a voltage level of an under_drive voltage to generate the under_drive voltage detection signal, and an under_drive voltage generator configured to generate the under_drive voltage in response to the under_drive voltage detection signal with a variable driving force in response to the external voltage detection signal.

Abstract: Disclosed is an internal voltage generating circuit that pumps charge to generate an internal driving voltage. The internal voltage generating circuit includes: a first oscillation signal generating unit that provides a first oscillation signal in response to a detected internal voltage and a predetermined test mode signal; a second oscillation signal generating unit that divides an external clock to provide a second oscillation signal having a variable oscillation period; and a switching unit that selects the first oscillation signal or the second oscillation signal in response to the predetermined test mode signal and provides the selected signal as a pumping period signal.

Abstract: The internal voltage generation circuit includes an internal voltage enable signal generation unit generating an internal voltage enable signal whose enable pulse width is controlled according to an external voltage. An internal voltage generation unit generates an internal voltage corresponding to a reference voltage according to the internal voltage enable signal. The internal voltage generation circuit generates an internal voltage according to an internal voltage enable signal whose enable pulse width is controlled in response to an external voltage, and thus current consumption is improved, and the internal voltage generation circuit provides a stable internal voltage.

Abstract: An internal voltage generating circuit includes a first detector that compares an internal voltage and a first reference voltage to output a first detection signal. A second detector compares a supply voltage and a second reference voltage to output a second detection signal. A loop selection oscillator performs an oscillation operation in response to the first detection signal, selects a first loop or a second loop for performing the oscillation operation in response to the second detection signal, and outputs an oscillation signal. A charge pump performs a pumping operation according to the output of the loop selection oscillator and generates the internal voltage.

Abstract: A sustained-release drug composition consisting essentially of microparticles of hyaluronic acid having a high molecular weight or an inorganic salt thereof and a protein or peptide drug encased in said microparticles, wherein the average size of said microparticles ranges from 0.1 to 40 ?m.

Abstract: A sustained-release drug composition consisting essentially of microparticles of hyaluronic acid having a high molecular weight or an inorganic salt thereof and a protein or peptide drug encased in said microparticles, wherein the average size of said microparticles ranges from 0.1 to 40 ?m.

Abstract: The present invention relates to a radial disk type ion mobility spectrometer, comprising: an ionizing chamber which is made of a cylindrical tube, and includes an inlet for supplying sample gas therethrough, an ionizing means for ionizing the supplied sample gas to generate ions having a predetermined polarity, and a slit formed by cutting away a part of a cylindrical wall corresponding to a predetermined width for discharging the ions therethrough; a shutter grid installed adjacent to the slit of the ionizing chamber for controlling passage of the ions through the slit; a drift chamber which is a hollow tube having a predetermined thickness and including an outer cylindrical wall having a predetermined diameter and an inner cylindrical wall having an inner diameter equal to an outer diameter to the ionizing chamber so that an annular space is formed between the inner and outer cylindrical walls, of which a part of the inner cylindrical wall corresponding to a width larger than that of the slit is cut away s

Abstract: A solid lipophilic microparticle having an average particle size ranging from 0.1 to 200 ?m, comprising a lipophilic substance, hyaluronic acid or an inorganic salt thereof and an active ingredient selected from the group consisting of a protein or peptide drug, retains the full activity of the active ingredient, and when formulated in the form of an oil dispersion or oil-in-water emulsion, it releases in an in vivo environment the active ingredient in a controlled manner over a long period.

Abstract: The present invention relates to a method of packaging optical parts for optical communication. According to the method of the present invention, there are advantages in that a packaging process for optical parts is automated to improve productivity and to obtain price competitiveness and uniformity of quality, and a high frequency heater for locally transferring heat to only a solder preform is used to minimize thermal deformation of areas except a soldering area, thereby achieving highly reliable packaging of the optical parts.

Abstract: A sustained-release drug composition consisting essentially of microparticles of hyaluronic acid having a high molecular weight or an inorganic salt thereof and a protein or peptide drug encased in said microparticles, wherein the average size of said microparticles ranges from 0.1 to 40 ?m.

Abstract: The present invention relates to a radial disk type ion mobility spectrometer, comprising: an ionizing chamber which is made of a cylindrical tube, and includes an inlet for supplying sample gas therethrough, an ionizing means for ionizing the supplied sample gas to generate ions having a predetermined polarity, and a slit formed by cutting away a part of a cylindrical wall corresponding to a predetermined width for discharging the ions therethrough; a shutter grid installed adjacent to the slit of the ionizing chamber for controlling passage of the ions through the slit; a drift chamber which is a hollow tube having a predetermined thickness and including an outer cylindrical wall having a predetermined diameter and an inner cylindrical wall having an inner diameter equal to an outer diameter to the ionizing chamber so that an annular space is formed between the inner and outer cylindrical walls, of which a part of the inner cylindrical wall corresponding to a width larger than that of the slit is cut away s

Abstract: The present invention relates to a method of packaging optical parts for optical communication. According to the method of the present invention, there are advantages in that a packaging process for optical parts is automated to improve productivity and to obtain price competitiveness and uniformity of quality, and a high frequency heater for locally transferring heat to only a solder preform is used to minimize thermal deformation of areas except a soldering area, thereby achieving highly reliable packaging of the optical parts.

Abstract: A solid lipophilic microparticle having an average particle size ranging from 0.1 to 200 &mgr;m, comprising a lipophilic substance, hyaluronic acid or an inorganic salt thereof and an active ingredient selected from the group consisting of a protein or peptide drug, retains the full activity of the active ingredient, and when formulated in the form of an oil dispersion or oil-in-water emulsion, it releases in an in vivo environment the active ingredient in a controlled manner over a long period.

Abstract: A sustained-release drug composition consisting essentially of microparticles of hyaluronic acid having a high molecular weight or an inorganic salt thereof and a protein or peptide drug encased in said microparticles, wherein the average size of said microparticles ranges from 0.1 to 40 &mgr;m.

Abstract: A microparticle having a particle size ranging from 0.5 to 300 .mu.m, which is prepared by dissolving an antigen or a mixture of antigens in an aqueous solution, adding a water-soluble substance thereto, and removing water to obtain a core particle and coating the core particle with a biodegradable polymer; and a single-shot vaccine formulation prepared by dispersing the microparticles in an injection medium.