Abstract: Provided is a composition for cancer treatment including phytosphingosine or a derivative thereof, or a pharmaceutically acceptable salt thereof as an active ingredient.

Abstract: A parallel-structured Raman optical amplifier includes a very wide gain band for use in Coarse Wavelength Division Multiplexing (CWDM) scheme—based optical transmission. The parallel-structured Raman optical amplifier for amplifying an input optical signal of a plurality of channels having different center wavelengths received via a single optical path includes: a demultiplexer for dividing the input optical signal into a plurality of optical signals, each of which is composed of at least one channel signal having an adjacent center wavelength, and outputting the divided optical signals to different output terminals; a plurality of Raman amplifiers for performing Raman-optical amplification upon the divided optical signals received from the demultiplexer; and a multiplexer for receiving individual optical signals from the plurality of Raman amplifiers, and outputting the received optical signals via a single optical path.

Abstract: An optical head has a beam input/output coupler on a planar waveguide and other parts including: a light transmitting element emitting a beam; a planar waveguide formed on a substrate and receiving the beam oscillated from the light transmitting element; a beam input/output coupler integrated as a thin film on a portion of the planar waveguide and receiving the beam through the planar waveguide to transmit the beam vertically toward a disc positioned above the planar waveguide or transmitting the beam reflected from the disc through the planar waveguide; and light receiving elements receiving the beam propagated to the planar waveguide through the beam input/output coupler.

Abstract: Provided are an apparatus and method for monitoring optical fibers of a passive optical network system including an optical line termination located in a central office, a remote node that is a local office, and optical network units on the subscriber side. The apparatus respectively allocates monitoring light wavelengths to optical network units such that optical fibers of the respective optical network units can be identified and monitored using the monitoring light wavelengths, combines a monitoring light having various wavelengths and a downward optical signal using the WDM coupler, and analyzes signal waveforms of the monitoring light having various wavelengths reflected from the optical network units, to detect the position of a defect generated on an optical line. Accordingly, it is possible to transmit optical signals and monitor the physical states of the optical fibers of the optical network units.

Abstract: Provided is a hybrid optical amplifier using a gain-clamped semiconductor optical amplifier enabling Raman amplification. The hybrid optical amplifier comprises a spool of optical fiber used as transmission line in the optical communication, a GCSOA amplifying optical signal input via the optical fiber and generating a self-oscillation laser beam for gain-clamping through the gain medium, and a backward pumping Raman optical amplifier inducing Raman amplification by emitting the self-oscillation laser beam generated by the GCSOA into the optical fiber. Therefore, the Raman amplification can be obtained with a relatively simple structure using the GCSOA.

Abstract: There are provided a method and system for monitoring an optical transmission line. The system for monitoring the optical transmission line includes: an OTDR (optical time-domain reflectometer) transmitting a monitoring light to an optical transmission line, measuring a reflected light or backscattered light to monitor the optical transmission line; an optical amplification unit amplifying the monitoring light transmitted on the optical transmission line by using a gain clamped optical amplifier; and a filter unit removing a component having a wavelength outside a wavelength band of the monitoring light from a backward ASE (amplified spontaneous emission) generated by the optical amplification unit. Accordingly, it is possible to extend an optical transmission line monitoring distance of the OTDR. As a result, it is possible to prevent deterioration of the performance of the OTDR because of the backward ASE.

Abstract: The present invention relates generally to a stocking system and its operating method. The stocking system comprises a shelf assembly, a first crane, and a second crane. The shelf assembly stores a plurality of cassettes. The first crane is installed at one side of the shelf assembly and loads/unloads the cassettes to/from the shelf assembly. The second crane is installed at the other side of the shelf assembly and loads/unloads the cassettes to/from the shelf assembly.

Abstract: A long-wavelength band (L-band) optical amplifier capable of maintaining a gain constant, thereby providing a stable optical output even when an optical power or a wavelength of a signal input thereto changes. The optical amplifier includes an amplifier which amplifies an input signal, and an amplified spontaneous emission (ASE) reflector which reflects backward ASE generated by the amplifier so that the backward ASE is fed back to the amplifier.

Abstract: The present invention provides an apparatus and method for compensating for the variation of a gain spectrum attributable to the temperature variation of a fiber amplifier, and a long-wavelength band dispersion-compensating hybrid amplifier equipped with the gain spectrum compensating apparatus. The apparatus includes a DCF located between a first amplification stage and a second amplification stage to compensate for dispersion of an optical signal output from the first amplification stage and perform Raman amplification of the optical signal using input pumping light; at least one pumping light provision means for providing forward or backward pumping light to the DCF; first and second temperature detection means for detecting temperature variations of the first and second amplification stages, respectively; and control means for controlling intensity of the pumping light of the pumping light provision means according to the detected temperature variations.