Abstract: Disclosed herein are an apparatus and method for updating an Internet-based malware detection engine using virtual machine scaling. The method may include creating a scaling group and an update group set based on a first virtual machine image, creating a second virtual machine image for a running virtual machine in response to occurrence of a snapshot event in the virtual update group run based on the first virtual machine image, modifying the scale-out image of the scaling group to the second virtual machine image, updating the scaling group by triggering a scale-out event and a scale-in event in the scaling group in response to occurrence of an update event, and modifying the scale-in image of the scaling group to the second virtual machine image.

Abstract: The present disclosure provides a process for effectively separating and removing by-products (light gas, C5-C6 hydrocarbon oil fraction, polyethylbenzene) contained in a substantial amount in addition to ethylbenzene as a target compound in an alkylation reaction product of a fluidized catalytic cracking off-gas to prepare ethylbenzene having high purity, and process economical efficiency may be secured by utilizing the polyethylbenzene as an absorbent or gasoline fraction, without requiring a transalkylation reaction for further producing ethylbenzene from polyethylbenzene.

Abstract: The present disclosure provides a process for effectively separating and removing by-products (light gas, C5-C6 hydrocarbon oil fraction, polyethylbenzene) contained in a substantial amount in addition to ethylbenzene as a target compound in an alkylation reaction product of a fluidized catalytic cracking off-gas to prepare ethylbenzene having high purity, and process economical efficiency may be secured by utilizing the polyethylbenzene as an absorbent or gasoline fraction, without requiring a transalkylation reaction for further producing ethylbenzene from polyethylbenzene.

Abstract: Disclosed is a method of efficiently separating 1,3-butadiene and methylethylketone, which are compounds of interest, from byproducts or impurities in the dehydration products of 2,3-butanediol so as to recover the compounds of interest at high purity.

Abstract: Disclosed is a method of preparing 1,3-butadiene and methyl ethyl ketone from 2,3-butanediol, including: a) providing a plurality of adiabatic reactors, which include a catalyst bed for dehydrating 2,3-butanediol, without a heat transfer medium, and are connected in series; b) introducing a stream including 2,3-butanediol at a temperature ranging from 200° C. to 400° C. into a first adiabatic reactor among the plurality of adiabatic reactors; c) dehydrating the 2,3-butanediol so as to be converted into 1,3-butadiene and methyl ethyl ketone and discharging a product stream including 1,3-butadiene and methyl ethyl ketone; d) heating the discharged product stream to to 200° C. to 400° C.; and e) introducing the heated product stream into a second adiabatic reactor so that 2,3-butanediol is further dehydrated and converted into 1,3-butadiene and methyl ethyl ketone and then discharging the product stream including 1,3-butadiene and methyl ethyl ketone.

Abstract: Disclosed is a method of preparing 1,3-butadiene and methyl ethyl ketone from 2,3-butanediol, including: a) providing a plurality of adiabatic reactors, which include a catalyst bed for dehydrating 2,3-butanediol, without a heat transfer medium, and are connected in series; b) introducing a stream including 2,3-butanediol at a temperature ranging from 200° C. to 400° C. into a first adiabatic reactor among the plurality of adiabatic reactors; c) dehydrating the 2,3-butanediol so as to be converted into 1,3-butadiene and methyl ethyl ketone and discharging a product stream including 1,3-butadiene and methyl ethyl ketone; d) heating the discharged product stream to 200° C. to 400° C.; and e) introducing the heated product stream into a second adiabatic reactor so that 2,3-butanediol is further dehydrated and converted into 1,3-butadiene and methyl ethyl ketone and then discharging the product stream including 1,3-butadiene and methyl ethyl ketone.

Abstract: Disclosed is a method of efficiently separating 1,3-butadiene and methylethylketone, which are compounds of interest, from byproducts or impurities in the dehydration products of 2,3-butanediol so as to recover the compounds of interest at high purity.

Abstract: An optical device with a quantum well is provided. The optical device includes an active layer made of a Group III-V semiconductor compound and having a quantum well of a bandgap grading structure in which conduction band energy and valence band energy change linearly with a slope with the content change of predetermined components while an energy bandgap between the conduction band energy and the valence band energy is maintained at a predetermined value; and two barrier layers, one of which is positioned on an upper surface of the active layer and the other is positioned on a lower surface of the active layer, and which are made of a Group III-V semiconductor compound and have higher conduction band energy and lower valence band energy than the active layer. A driving voltage is decreased and luminous efficiency and reliability are enhanced.

Abstract: A method of fabricating a one-way transparent optical system designed to transmit almost 100% of internal light while effectively blocking radiation of external light. The method includes: forming bead-shaped light absorbing elements; dispersing the light absorbing elements over a soft transparent film; and curing the soft transparent film to fix the dispersed light absorbing elements onto the transparent film.

Abstract: An optical device with a quantum well is provided. The optical device includes an active layer made of a Group III-V semiconductor compound and having a quantum well of a bandgap grading structure in which conduction band energy and valence band energy change linearly with a slope with the content change of predetermined components while an energy bandgap between the conduction band energy and the valence band energy is maintained at a predetermined value; and two barrier layers, one of which is positioned on an upper surface of the active layer and the other is positioned on a lower surface of the active layer, and which are made of a Group III-V semiconductor compound and have higher conduction band energy and lower valence band energy than the active layer. A driving voltage is decreased and luminous efficiency and reliability are enhanced.

Abstract: An optical device with a quantum well is provided. The optical device includes an active layer made of a Group III-V semiconductor compound and having a quantum well of a bandgap grading structure in which conduction band energy and valence band energy change linearly with a slope with the content change of predetermined components while an energy bandgap between the conduction band energy and the valence band energy is maintained at a predetermined value; and two barrier layers, one of which is positioned on an upper surface of the active layer and the other is positioned on a lower surface of the active layer, and which are made of a Group III-V semiconductor compound and have higher conduction band energy and lower valence band energy than the active layer. A driving voltage is decreased and luminous efficiency and reliability are enhanced.

Abstract: A laser diode is provided. The laser diode has a structure in which reflective index of an n-cladding layer formed on a first face of the active layer is higher than that of a p-cladding layer formed on a second face. This asymmetric waveguide structure suppresses extension of field into the p-cladding layer thus reducing free carrier absorption in the p-cladding layer.

Abstract: A method of fabricating a one-way transparent optical system designed to transmit almost 100% of internal light while effectively blocking radiation of external light. The method includes: forming bead-shaped light absorbing elements; dispersing the light absorbing elements over a soft transparent film; and curing the soft transparent film to fix the dispersed light absorbing elements onto the transparent film.

Abstract: A laser diode is provided. The laser diode has a structure in which reflective index of an n-cladding layer formed on a first face of the active layer is higher than that of a p-cladding layer formed on a second face. This asymmetric waveguide structure suppresses extension of field into the p-cladding layer thus reducing free carrier absorption in the p-cladding layer.

Abstract: An optical device with a quantum well is provided. The optical device includes an active layer made of a Group III-V semiconductor compound and having a quantum well of a bandgap grading structure in which conduction band energy and valence band energy change linearly with a slope with the content change of predetermined components while an energy bandgap between the conduction band energy and the valence band energy is maintained at a predetermined value; and two barrier layers, one of which is positioned on an upper surface of the active layer and the other is positioned on a lower surface of the active layer, and which are made of a Group III-V semiconductor compound and have higher conduction band energy and lower valence band energy than the active layer. A driving voltage is decreased and luminous efficiency and reliability are enhanced.