Abstract: An optical fiber unit for air blown installation includes at least one optical fiber having a core layer and a clad layer, a protective layer coated on the surface of the optical fiber; and protrusions made of polymer resin and formed on the outer circumference of the protective layer in a banded shape. The protrusions may be formed either by supplying polymer resin to the outer circumference of the optical fiber with passing the optical fiber through an extrusion dice in which grooves of a predetermined shape are formed on a hollow inner circumference thereof, or by supplying polymer resin to the outer circumference of the optical fiber through nozzles with moving the optical fiber in a longitudinal direction.

Abstract: An Outside Vapor Deposition (OVD) apparatus for making an optical fiber preform with uniform deposition of silica particles through uniform heating to the overall length of the preform includes a mandrel having a predetermined length and driven to rotate and a burner for emitting a combustion gas together with a combustion gas toward the mandrel and burning the combustion gas to make silica particles to that the silica particles are deposited on a surface of the mandrel, wherein the burner has a length corresponding to the length of the mandrel and provides uniform temperature throughout the overall length of the mandrel at the same time.

Abstract: Disclosed is installation of an optical fiber composite electric power cable. An installation method of an optical fiber composite electric power cable includes installing an electric power cable including a conductor and an air-blown installation tube therein at an installation region; connecting tubes of adjacent electric power cables to each other, in an electric power cable connection box; and installing an optical fiber unit into the connected tubes by air pressure. Also, a cable structure used for installing the optical fiber composite electric power cable includes a conductor for electric power transmission; an insulator surrounding the conductor; an air-blown installation tube provided out of the insulator; and a corrosion-protective layer provided to an outermost layer of the cable.

Abstract: An outer and inner diameter measuring method for a transparent tube in a non-contact manner includes the steps of irradiating a light having a linear sectional shape, inclined at a pre-determined angle with respect to a plane perpendicular to a length direction of a transparent tube, to the transparent tube; obtaining a light beam pattern formed since the light having a linear sectional shape is intercepted and refracted by the tube; obtaining an inner diameter of the tube by extracting inner diameter information of the tube from the obtained light beam pattern; and obtaining an outer diameter from a light beam pattern refracted by the tube, thereby calculating the outer and inner diameters together.

Abstract: Disclosed are an insulated electric wire with partial discharge resistance and a composition for manufacturing the same. The insulated electric wire with partial discharge resistance according to the present invention includes an insulating base resin constituting a basic material of an insulated electric wire; an inorganic insulator included at a content of 5 to 40 parts by weight on the basis of 100 parts by weight of the insulating base resin; and a rubbery modifier included at a content of 0.1 to 30 parts by weight on the basis of 100 parts by weight of the insulating base resin to improve flexibility of an insulated electric wire. The insulated electric wire with partial discharge resistance of the present invention may be useful to prevent occurrence of cracks caused by winding of an insulated electric wire since the insulated electric wire has a sufficient partial discharge resistance and also enhances sufficient physical properties such as flexibility, pliability, bendability, elongation, etc.

Abstract: The present invention relates to an apparatus for acquiring image information using array of image acquisition units, each having an optical device. The apparatus for acquiring image information includes a geometric array of image acquisition units, each having optical device generating source electrical signal depending on image intensity of a subject, and an image signal output unit for receiving electrical signal generated from the array and generating source electrical signal to process analog image. According to the present invention, costs required for building a system for acquiring image information may be reduced. In addition, it is possible to fast acquire image information, thereby usefully applying to image information acquisition in fast total inspection process. Furthermore, various values with respect to a dimension of the subject are easily calculated by using a geometry location and dimension information of the image acquisition units.

Abstract: Disclosed is the preparation of organic/inorganic hybrid particles comprising magnesium hydroxide cores and tethered copolymer chains whose composition can be selected to allow dispersion in targeted plastic materials, thereby providing improved mechanical, electrical and flame retardant properties. Processes for preparing the same are also disclosed.

Abstract: The mold clamping unit comprises a column mounted in a transfer means and moving in forward and backward direction; a mold clamping piston in which clamping operation and clamping-releasing operation are performed; plurality of column teeth disposed on a surface of the column along an axial direction of the column; center bore provided in a central of the mold clamping piston; clamping tooth seating groove with a plurality of clamping teeth inside the mold clamping piston contacting the center bore; rotating plate with plurality of clamping tooth guide grooves separated from the clamping teeth in the axial direction of the column; and a teeth rod positioned in each of the clamping tooth guide groove, wherein each teeth rod is connected to each clamping teeth during the rotation of the rotating plate, for moving each clamping tooth in a central or radial direction of the rotating plate and clamping of the clamping tooth and the column can proceed.

Abstract: A communication cable includes at least one twisted wire pair formed by twisting a plurality of insulation-coated wires; a sheath surrounding the twisted wire pair; and a protrusion formed on an outer surface of the sheath. This communication cable may prevent alien crosstalk particularly at high-speed transmission so that transmission characteristics of the communication cable may be stably kept.

Abstract: Disclosed is a low-attenuation single-mode optical fiber having a photoconductive core and a clad, which shows very low OH concentration in MFD (Mode Field Diameter) region. The optical fiber includes a core positioned at its center for photoconduction, and a dehydrated clad and a base clad which are coated on the clad in order. The dehydrated clad has a substantially identical refractive index to the base clad. A refractive index of the core is greater than those of the dehydrated clad and the base clad. The dehydrated clad has a relatively lower OH concentration than the base clad. The region composed of the core and the dehydrated clad has an MFD region at which OH concentration is less than 0.8 ppb.

Abstract: An optical fiber unit installation apparatus having a unit for preventing a fluid from flowing backward toward entrance of the optical unit to prevent fluid leakage while the optical fiber unit is installed using air pressure is disclosed. The apparatus includes an optical fiber unit supplier; a blowing head having an entrance for introduction of an optical fiber unit supplied from the supplier, and an exit communicated with the entrance and combined with a tube for air pressure installation; a pressing unit for applying air pressure to the optical fiber unit introduced into the blowing head to insert the optical fiber unit into the tube; and a fiber sealing unit, an aggregation of fur-type elastic fibers, mounted in an advancing path of the optical fiber unit through the blowing head to prevent fluid leakage by surrounding the optical fiber unit with fiber ends contacted thereon.

Abstract: Disclosed is a loose tube optical cable having an unstranded structure, which includes a tensile strength member longitudinally elongated and having a central axis deviated from the center of the optical cable, a loose tube optical fiber unit longitudinally elongated without intended twist against the tensile strength wire, and a cable coating for wrapping an aggregation in which the tensile strength member and the loose tube optical fiber unit are straightly aggregated. By suitably selecting geometric parameters of the tensile strength member and the loose tube optical fiber unit, the center of mass of the aggregation is positioned within the tensile strength member and the maximum modulus of elongation of the optical fiber is restricted within a predetermined range in a predetermined bending radius.

Abstract: For flux coating of a heat exchanger tube made of aluminum, firstly, the heat exchanger tube is dipped in a storage tank containing a mixture of binder and solvent to coat the mixture on a surface of the heat exchanger tube, thereby forming a first coating layer on the surface of the heat exchanger tube. Then, flux powder is sprayed to the surface of the heat exchanger tube on which the first coating layer is formed, thereby forming a second coating layer. After that, a thickness of the heat exchanger tube on which the second coating layer is formed is controlled. Then, the thickness-controlled heat exchanger tube is heated to 150° C. or below so as to remove the solvent from the second coating layer.

Abstract: Disclosed is a superconducting power cable capable of quench detection, and a quench detection system using the superconducting power cable. The superconducting power cable capable of quench detection includes a former; a superconducting conductor layer composed of a superconducting wire and surrounding the former; a conductor layer quench detection coil interposed between the former and the superconducting conductor layer and surrounding the former; an insulating layer surrounding the superconducting conductor layer; and a shielding layer surrounding the insulating layer. This superconducting power cable may detect quench generated during its operation in real time.

Abstract: Disclosed is an optical fiber suitable for an optical transmission line used in WDM system, particularly a single-mode optical fiber whose zero-dispersion wavelength is positioned in a short wavelength band (less than 1,370 mm) so as to enable high-speed mass-storage signal transmission over S-C-L bands (1,460˜1,625 nm) and whose dispersion value and effective sectional area are optimized. In the optical fiber, a dispersion value is at least 9 ps/nm-km at 1,460 nm, an effective sectional area is 45-65 ?m2 at 1,460 rim, a zero-dispersion wavelength exists at 1,370 nm or less, and a dispersion slope is positive. In addition, RDS (Relative Dispersion Slope) is 0.0032˜0.0038 nm?1 at 1,550 nm. Thus, the optical fiber enables to repress non-linearity and signal distortion to the maximum during 320 km repeaterless transmission with a transmission rate of 10 Gb/s or more over S-C-L bands, a channel spacing of 50 GHz or less, 16 channels, and a signal power of 0 dBm/ch or 2 dBm/ch.

Abstract: Disclosed is a tube for air blown installation and a tube cable using the same. The tube includes an outer layer made of polyethylene; and an inner layer co-extruded on an inner side of the outer layer and made of a mixture of polyethylene and siloxane, wherein the inner layer has a static coefficient of friction of 0.05 to 0.20, wherein the inner and outer layers respectively have a thickness equal to or less than 0.8 mm, and wherein no damage is caused in the tube having a length of 500 m when a pressure of 10 bars is applied thereto for 24 hours. The tube cable includes a sheath and a plurality of tube bundles. Each tube bundle is substantially identical to the above tube.

Abstract: An apparatus for manufacturing a trapezoidal wire using two-set shaping rollers has a body rotating about a central axis at a predetermined speed, a plurality of first shaping roller sets installed along an outer circumference of the body, each first shaping roller set including an upper roller and a lower roller and a shaping portion, into which a wire is inserted to be processed, between the upper roller and the lower roller, and a plurality of second shaping roller sets arranged after the first shaping roller sets along the outer circumference of the body and in a direction in which the wire moves, each second shaping roller set comprising an upper roller and a lower roller and a shaping portion, into which the wire is inserted to be processed again, between the upper roller and the lower roller, wherein wires processed by the first and second shaping roller sets while passing therethrough are stranded by the rotating body.

Abstract: Disclosed is an optical fiber suitable for WDM system, particularly whose zero-dispersion wavelength is positioned in a short wavelength band less than 1,300 mm. In the optical fiber, dispersion has a positive value, not zero, at 1,310 nm, and a dispersion slope is positive at 1,550 rim with dispersion of 25 ps/nm-km or less. In addition, an effective sectional area is 65 ?m2 or less at 1,310 rim, and 80 ?m2 or less at 1,550 nm. Thus, though a transmission signal is Raman-amplified at a wavelength band of 1,300 to 1,700 nm, transmission characteristics are not deteriorated due to crosstalk between pump signals. In addition, since the optical fiber has smaller effective sectional area than a general single-mode optical fiber with having substantially the same dispersion feature, it gives better Raman gain efficiency than a general single-mode optical fiber.

Abstract: Disclosed is a single-mode optical fiber suitable for and optical transmission line used in WDM (Wavelength Division Multiplexing) system, which has low dispersion slope, sufficient dispersion value and large effective section area over S-, C- and L-band (1460˜1625 nm) to enable high-speed, large-capacity signal transmission. The optical fiber uses the wavelength region from 1460 to 1625 nm, and the optical fiber also has a dispersion value of 0.1˜3.0 ps/nm-km, more preferably 0.3˜2.4 ps/nm-km, at 1460 nm, a dispersion value of 3.0˜5.5 ps/nm-km, more preferably 3.2˜5.2 ps/nm-km, at 1550 nm, and a dispersion value of 4.5˜8.0 ps/nm-km, more preferably 4.8˜7.7 ps/nm-km, at 1625 nm. In addition, the optical fiber has a dispersion slope of 0.023˜0.05 ps/nm-km2 at 1550 nm, an effective sectional area of 35˜50 ?m2 at 1550 nm, an effective section area of 35˜50 ?m2 at 1460 nm.

Abstract: Disclosed is an optical transmission system capable of transmitting optical signals of E-band and other bands through one optical fiber. The system includes a first thin film filter for receiving optical signals of E-band and other bands at both sides thereof respectively, and multiplexing the optical signals of both E-band and other bands by selectively transmitting wavelength ranges received at one side, reflecting wavelength ranges received at the other side, and then coupling the optical signals of both E-band and other bands; an optical fiber for transmitting the optical signals multiplexed by the first thin film filter to a receiving portion; and a second thin film filter for selectively separating and demultiplexing the E-band and other bands from the optical signals transmitted through the optical fiber.