Abstract: Provided is a hybrid passive optical network (PON) system. The hybrid PON system of wavelength division multiplexing (WDM)/time division multiplexing (TDM) may include an optical line terminal (OLT) and an optical network unit (ONU). The OLT and the ONU may transmit a signal based on wavelength reuse using a seed light source and a reflective modulator. The light source may include a seed light source having a single wavelength, two seed light sources having different wavelength bands, and a light source having a wavelength tunable characteristic.

Abstract: A network apparatus as well as a data compression and data recovery method thereof using compressed sensing (CS). According to an exemplary embodiment, the data compression and recovery method may include compressing raw digital signals by using CS; modulating and transmitting the compressed raw digital signals; receiving and demodulating the modulated raw digital signals; and recovering the raw digital signals by decompressing, by using CS, the demodulated raw digital signals.

Abstract: There are provided a method of allocating upstream bandwidth resources and a method of transmitting upstream data in an orthogonal frequency division multiple access-open optical subscriber network. The method of allocating an upstream bandwidth resource according to an embodiment of the invention includes receiving queue status information from each optical network unit (ONU), and allocating an upstream bandwidth by providing to each ONU a 2-D upstream bandwidth map on a subcarrier-time resource through a frame synchronized at constant cycles, based on the queue status information received from each ONU.

Abstract: A converged passive optical network (CPON) and a data transmission method are disclosed. The CPON is a combination of a time division multiple access-passive optical network (TDMA-PON) and an orthogonal frequency division multiple access-passive optical network (OFDMA-PON) and is able to dynamically controlling a bandwidth for upstream signal transmission through allocation of multiple subcarriers to each single optical network unit (ONU).

Abstract: Provided is a method of selecting a wavelength of an optical network unit including selecting a pre-loaded default wavelength as an available wavelength candidate or the wavelength that has been changed when a preset wavelength changing condition is satisfied as the available wavelength candidate, acquiring frame synchronization for a downstream signal having the same wavelength as the selected available wavelength candidate, and transmitting a registration request message to an optical line terminal (OLT) from which the downstream signal has been transmitted when the frame synchronization is acquired, assigning the available wavelength candidate to an available wavelength used for communication with the OLT and registering the terminal in the OLT when a registration allowance message is received from the OLT.

Abstract: An orthogonal frequency division multiple access-passive optical network including a plurality of optical network units each configured to generate orthogonal frequency division multiplexed signals, which are allocated thereto, based on a central frequency for frequency division multiplexing that is allocated in advance, and to use the generated signals in upstream transmission.

Abstract: Provided is an optical transmission apparatus and method for uplink transmission in an orthogonal frequency division multiple access-passive optical network (OFDMA-PON), wherein the optical transmission apparatus includes a digital signal processor to output a baseband orthogonal frequency division multiplexing (OFDM) signal, a tone generator to generate a dithering tone, a synthesizer to synthesize the dithering tone and the baseband OFDM signal, and an optical source to output an output light in which a spectrum width is increased to be greater than a spectrum width of a carrier light based on the baseband OFMD signal synthesized with the dithering tone.

Abstract: The present invention relates to a technology for measuring a nonlinear parameter of an object to be measured, and more particularly, to an apparatus and method for measuring a nonlinear parameter of an object to be measured.

Abstract: An OLED display device with a passivation film formed between a sealing member and a pad portion through a structural alteration of the sealing member and first and second protective layers prevents deterioration of image quality and a driving faults caused by short circuits and electro-static discharge.

Abstract: A modulation method of an optical modem and a signal transmission apparatus performing the method are disclosed. The modulation method of the optical modem includes an optical interface providing a signal to a light source, a photo detector receiving reflected light by an optical link when output light from the light source based on the provided signal is reflected by the optical link, the photo detector measuring and determining characteristics of the optical link using the reflected light, and the optical modem determining a power level and a modulation method for each subcarrier based on the characteristics of the optical link.

Abstract: A software-defined networking (SDN) method. The SDN method according to an exemplary embodiment may be used in managing and operating SDN-based network resources in an optical communications network, a fixed mobile convergence subscriber network, a wired broadband subscriber network, a distributed mobile communications base station network, etc.

Abstract: Provided are a user-selectable laser and an optical transmitter including the same. The user-selectable laser is an external cavity laser including a semiconductor laser diode for outputting an optical signal, and a wavelength selection filter. The user-selectable laser may allow a user to select a wavelength selection filter which is optically coupled with the semiconductor laser diode and selectively causes oscillation at the wavelength of an optical signal output from the semiconductor laser diode.

Abstract: A magnetostrictive phased array transducer for transducing shear horizontal bulkwaves including a plurality of magnetostrictive members each having a bottom surface of a plate-shaped structure made of a ferromagnetic material, which is mounted to be adhered closely to the surface of a mounting place; an insulator disposed on a side surface of each magnetostrictive member; a meander coil having a plurality of coil lines extended in the direction parallel with the bottom surface on each insulator, wherein adjacent coil lines are connected so that current flows in the opposite directions to each other, thereby generating a dynamic magnetic field with respect to each magneto strictive member; and a magnet mounted to generate a static magnetic field perpendicular to the dynamic magnetic field. When the current is supplied to the meander coil, a plurality of magnetostrictive members generate a plurality of shear horizontal bulkwaves while being deformed by the magnetostriction effect.

Abstract: A detachable optical transceiver includes an optical part configured to convert an electric signal into an optical signal and transmit the optical signal, or to convert an optical signal into an electric signal and output the electric signal; and an electronic circuit part configured to amplify an electric signal input from a host board and output the amplified electric signal to the optical part, and to amplify an electric signal output from the optical part and output the amplified electric signal to the host board, wherein the optical part and the electronic circuit part are formed to have housings and the optical part and the electronic circuit part are connected and disconnected via connectors formed on the respective housings.

Abstract: An OLED display device with a passivation film formed between a sealing member and a pad portion through a structural alteration of the sealing member and first and second protective layers prevents deterioration of image quality and a driving faults caused by short circuits and electro-static discharge.

Abstract: An apparatus and method for skipping fractional motion estimation (FME) in high efficiency video coding (HEVC) are disclosed. The apparatus includes a current sum of absolute differences (SAD) acquisition unit, a redundancy determination unit, and a motion estimation skip unit. The SAD acquisition unit acquires the SAD from an integer motion estimation (IME) unit when the IME unit performs IME on a coding tree block (CTB). The redundancy determination unit determines whether or not the CTB is an estimated redundant block using the current SAD. The motion estimation skip unit provides an FME unit with an FME skip signal of the CTB depending on whether or the CTB is an estimated redundant block.

Abstract: A method of fabricating a micro drill, which includes a drill part for machining a hole and a shank part fixed to a motor, the drill part and the shank part being made of different materials. The method includes the steps of forming a drill part-forming powder compact having a recess in one end thereof, and forming a shank part-forming powder compact having a protrusion, the protrusion intended to be fitted into the recess of the drill part-forming powder compact, forming an assembly of the drill part-forming powder compact and the shank part-forming powder compact, with the protrusion fitted into the recess, and simultaneously sintering the assembly of the drill part-forming powder compact and the shank part-forming powder compact.

Abstract: The present invention relates to an open optical access network system in which one optical access network is open to enable a plurality of service providers and a plurality of subscribers to simultaneously use the optical access network, to thereby improve the efficiency of using the optical access network, wherein each subscriber can be provided with a plurality of different services from the plurality of service providers, thereby enabling the flexible selection of services and the flexible change in services, thus improving the efficiency of using an optical infrastructure.

Abstract: Provided is a method of selecting a wavelength of an optical network unit including selecting a pre-loaded default wavelength as an available wavelength candidate or the wavelength that has been changed when a preset wavelength changing condition is satisfied as the available wavelength candidate, acquiring frame synchronization for a downstream signal having the same wavelength as the selected available wavelength candidate, and transmitting a registration request message to an optical line terminal (OLT) from which the downstream signal has been transmitted when the frame synchronization is acquired, assigning the available wavelength candidate to an available wavelength used for communication with the OLT and registering the terminal in the OLT when a registration allowance message is received from the OLT.

Abstract: There are provided a method of allocating upstream bandwidth resources and a method of transmitting upstream data in an orthogonal frequency division multiple access-open optical subscriber network. The method of allocating an upstream bandwidth resource according to an embodiment of the invention includes receiving queue status information from each optical network unit (ONU), and allocating an upstream bandwidth by providing to each ONU a 2-D upstream bandwidth map on a subcarrier-time resource through a frame synchronized at constant cycles, based on the queue status information received from each ONU.