Abstract: Provided is a semiconductor device comprising an active region on a substrate and including first and second sidewalls extending in a first direction and an epitaxial pattern on the active region, wherein the epitaxial pattern includes first and second epitaxial sidewalls extending from the first and second sidewalls, respectively, the first epitaxial sidewall includes a first epitaxial lower sidewall, a first epitaxial upper sidewall, and a first epitaxial connecting sidewall connecting the first epitaxial lower sidewall and the first epitaxial upper sidewall, the second epitaxial sidewall includes a second epitaxial lower sidewall, a second epitaxial upper sidewall, and a second epitaxial connecting sidewall connecting the second epitaxial lower sidewall and the second epitaxial upper sidewall, a distance between the first and second epitaxial upper sidewalls decreases away from the active region, and the first and second epitaxial lower sidewalls extend in parallel to a top surface of the substrate.

Abstract: Provided is a Raman scattering measurement apparatus including a light source which emits light to smoke particles, a filter configured to block light which is incident to the smoke particles and passes through the particle and to allow Raman scattered light to pass therethrough, and a photodetector which detects the Raman scattered light passing through the filter in order to distinguish fire smoke generated due to a true fire from non-fire smoke generated due to daily life or industrial activity. The present invention also provides a fire determination apparatus including a unit which reads a Raman shift from Raman scattered light detected by the photodetector of the Raman scattering measurement apparatus, estimates a smoke component from the read Raman shift, and determines fire/non-fire from the estimated smoke component and a method thereof.

Abstract: A fluid stabilizing control method of an axial compressor is provided, which includes driving to drive the axial impeller, and stall controlling to suppress or prevent an occurrence of a stall that may transpire during rotation of the axial impeller by supplying highly-pressurized compressed air into the casing through a stall controller according to a predetermined time and volume. Accordingly, a stall may be suppressed or prevented, the occurrence of a stall that may transpire when a threshold point is exceeded by an unexpected event during driving in a low-flow high-pressure section on a performance curve, in which efficiency is high. Additionally, since an air injection method for suppressing the stall is properly applied, an amount of power expended for the stall control may be reduced while supply of the high-pressure compressed air is minimized, thereby achieving economically feasible stall control.

Abstract: A fluid stabilizing control method of an axial compressor is provided, which includes driving to drive the axial impeller, and stall controlling to suppress or prevent an occurrence of a stall that may transpire during rotation of the axial impeller by supplying highly-pressurized compressed air into the casing through a stall controller according to a predetermined time and volume. Accordingly, a stall may be suppressed or prevented, the occurrence of a stall that may transpire when a threshold point is exceeded by an unexpected event during driving in a low-flow high-pressure section on a performance curve, in which efficiency is high. Additionally, since an air injection method for suppressing the stall is properly applied, an amount of power expended for the stall control may be reduced while supply of the high-pressure compressed air is minimized, thereby achieving economically feasible stall control.