Abstract: An embodiment of the present specification provides a method for preparing a catalyst for preparing a carbon nanotube, comprising: (a) dissolving a main catalyst precursor, a support precursor, a cocatalyst precursor and a precipitation inhibitor in a solvent to prepare a precursor solution; and (b) pyrolyzing the precursor solution by spraying the precursor solution into a reactor, wherein a mole fraction of the precipitation inhibitor to the cocatalyst precursor is 0.1 to 1.5.

Abstract: The present disclosure relates to a semiconductor device, and a test apparatus and method thereof, capable of accurately detecting a defect by using a plurality of resistor circuits in a test process. The test apparatus of a semiconductor device according to an aspect of the present disclosure may include semiconductor chips each including an external resistor circuit disposed to be dispersed along an outer region of a chip and an internal resistor circuit disposed in an inner region of the chip in order to test cracks, and test equipment that drives the external resistor circuit and the internal resistor circuit and compares an output of the external resistor circuit with an output of the internal resistor circuit to detect whether a defect occurs in each of the semiconductor chips.

Abstract: The present disclosure relates to a semiconductor device, and a test apparatus and method thereof, capable of accurately detecting a defect by using a plurality of resistor circuits in a test process. The test apparatus of a semiconductor device according to an aspect of the present disclosure may include semiconductor chips each including an external resistor circuit disposed to be dispersed along an outer region of a chip and an internal resistor circuit disposed in an inner region of the chip in order to test cracks, and test equipment that drives the external resistor circuit and the internal resistor circuit and compares an output of the external resistor circuit with an output of the internal resistor circuit to detect whether a defect occurs in each of the semiconductor chips.

Abstract: A method of removing hydrous silica from bentonite includes irradiating an ultrasonic wave after preparing slurry by putting the bentonite and a sodium compound into distilled water or deionized water, adding the distilled water or the deionized water to the slurry, into which the ultrasonic wave is irradiated, to dilute and centrifugate the slurry, and drying a supernatant obtained through the centrifugation.

Abstract: Disclosed are a drive wheel bearing and a method of manufacturing the same.

Abstract: Disclosed are a drive wheel bearing and a method of manufacturing the same.

Abstract: A method of removing hydrous silica from bentonite includes irradiating an ultrasonic wave after preparing slurry by putting the bentonite and a sodium compound into distilled water or deionized water, adding the distilled water or the deionized water to the slurry, into which the ultrasonic wave is irradiated, to dilute and centrifugate the slurry, and drying a supernatant obtained through the centrifugation.

Abstract: A method of physicochemical leaching valuable metals is able to increase the leaching rate of nickel and magnesium contained in laterites, nickel ores, with a low concentration acid solution by using mechano-chemical effect. That is a method to add external energy to laterites containing nickel and magnesium to physically disintegrate their crystals and exposure nickels captured inside of the crystals to leach nickel and magnesium with a low concentration acid solution. It is a useful method to solve conventional problems such as the high energy cost of pyrometallurgical treatment and excessive use of strong acids of hydrometallurgical method.

Abstract: A call processing method capable of home-zone additional service in a mobile communication system, in particular, which gives subscribers a discount in accounting without an additional equipment if the subscribers call within previously registered areas. According to the call processing method capable of home-zone additional service in the mobile communication service of the invention, the subscriber can be provided with the home-zone additional service with low cost, thereby enhancing customer satisfaction.

Abstract: A call processing method capable of home-zone additional service in a mobile communication system, in particular, which gives subscribers a discount in accounting without an additional equipment if the subscribers call within previously registered areas. According to the call processing method capable of home-zone additional service in the mobile communication service of the invention, the subscriber can be provided with the home-zone additional service with low cost, thereby enhancing customer satisfaction.

Abstract: The present invention relates to a vapor pressure control system which include a canister containing activated carbon therein, a tank pressure sensor connected to a fuel tank to sense internal vapor pressure of the fuel tank, a control valve mounted in a path from the fuel tank to the canister to control the internal vapor pressure of the fuel tank, and a cut valve mounted below a filler cap to lead the vapor flowing backward from the fuel tank to the canister, so that vehicles can have vapor stability and reduce air pollution.

Abstract: A structure for guiding fuel evaporation gases in a canister for automobiles is disclosed. The gas guide structure in the canister of this invention is free from a partition, which has been typically arranged in the upper section inside the upper case of the canister, but has a mounting nipple which is provided on the top center of the upper case. An evaporation gas guide unit is tightly fitted into the mounting nipple. The gas guide unit comprises a nipple holder and fitting part which are preferably cast as a single structure. The nipple holder has the gas inlet and outlet nipples, while the fitting part is fitted into the mounting nipple in order to airtightly mount the unit to the canister. The structure appropriately controls flow of the evaporation gases inside the canister filled with active charcoal, thereby preventing quick failure of the charcoal and lengthening the expected life span of the canister, and improving the durability of an evaporation gas control device.