Abstract: The present invention relates to a multi-core fuel rod for research reactor and, more particularly, to a multi-core fuel rod for research reactor in which monolithic fuel cores made of uranium-molybdenum alloy are disposed in an aluminum matrix in a multi-core form. The multi-core fuel rod in accordance with the present invention provides a minimized contact surface area between nuclear fuel and aluminum, and reduces the formation of pores and swelling by restraining formation of reaction layer to avoid excessive reaction between the fuel and aluminum. Therefore, improved stability of nuclear fuel can be obtained by minimizing temperature rise as well as achieving high density and thermal conductivity of the fuel.

Abstract: A method of manufacturing a tunable wavelength optical filter. The method includes steps of forming a first sacrificial oxide film for floating a lower mirror on a semiconductor substrate; sequentially laminating conductive silicon films and oxide films for defining a mirror region on the first sacrificial oxide film in a multi-layer and laminating another conductive silicon film to form a lower mirror; sequentially laminating conductive silicon films and oxide films for defining the mirror region on a second sacrificial oxide film in a multi-layer and laminating another conductive silicon film to form an upper mirror and forming an optical tuning space between the lower mirror and the upper mirror and etching the first sacrificial oxide film and the second sacrificial oxide film such that the lower mirror is floated on the semiconductor substrate.

Abstract: An oxadiazole compound and process of making same, is represented by Formula I: wherein R1 represents a substituted or unsubstituted straight, branched, or cyclo-alkyl group having at least two carbon atoms, and R2 represents an alkyl, aryl, or heteroaryl group.

Abstract: A method for the preparation of N-pyrazolylamidoximes of the general formula I R1 and R2 independently represent an alkyl, aryl, or heteroaryl group, comprises reacting a 5-(?-ketoalkyl)-3-substituted-1,2,4-oxadiazoles of the general formula II with hydrazine.

Abstract: Provided is a Fabry-Perot type wavelength tunable optical filter, comprising a first mirror; a second mirror located over the first mirror; a driving body located over the first mirror, and having both ends fixed to the first mirror through a spacer; a plurality of electrodes, each formed on both ends of the driving body; a rod structure connecting a center of the driving body and the second mirror; a plurality of fixing means, each fixed to the first mirror at both sides of the rod structure through the spacer; and a plurality of elastic bodies connecting the rod structure with the plurality of fixing means and acting as a rotational axis. And the mirror is driven by the rod structure acting as a lever that has an elastic body as a rotational axis, when warping is generated by electro-thermal expansion, electromagnetic force or external force. Thereby the mirror can be driven in the larger wavelength tunable range and the low power consumption.

Abstract: A plate-type nuclear fuel having regularly arranged coarse particles of a gamma-phase U—Mo or U—Mo—X alloy and a fabrication method thereof and, more particularly, to a plate-type nuclear fuel having coarse spherical particles of a stable gamma-phase U—Mo or U—Mo—X alloy arranged regularly on an aluminum cladding in at least one layer and a fabrication method thereof. Operation limit power, high temperature irradiation stability and performance are advantageously improved by preventing excessive reaction between a nuclear fuel and aluminum matrix through minimization of the area of interaction layers between the fuel and aluminum matrix, minimizing pores and swelling by restraining reaction layer formation of an intermetallic compound, and maintaining high thermal conductivity to transfer internal temperature of the nuclear fuel smoothly.

Abstract: A wavelength tunable filter capable of being driven such that reflecting mirrors move more distant as well as closer by using the principle that a direction of the electromagnetic forces changes depending on the direction of the current flowing perpendicular to the external magnetic field. According to the wavelength tunable filter of the present invention, when it is necessary to have the wavelength tuning range and mechanical structure similar to the conventional wavelength tunable filter driven in only one direction, it is possible to lower the maximum force needed to drive the filter to a half, and reduce a probability that a pull-in phenomenon occurs. On the other hand, it is possible to reduce a wavelength change time of the element by increasing a resonant frequency when the same wavelength tuning ranges are implemented by using the same maximum driving forces.

Abstract: An active type tunable wavelength optical filter having a Fabry-Perot structure is disclosed. A tunable wavelength optical filter which comprises a lower mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion; an upper mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion and which is spaced away from the lower mirror by a predetermined distance; a connecting means for connecting and supporting the lower mirror and the upper mirror to a semiconductor substrate; and electrode pads for controlling the gap between the lower mirror and the upper mirror by an electrostatic force and the method of manufacturing the same are provided.

Abstract: Provided is a wavelength tunable optical filter of a micro-electro-mechanical system (MEMS). The wavelength tunable optical filter comprises two optical fibers or optical waveguides having their optical axes aligned to each other, two lens for collimating light at leading ends of the optical fibers or optical waveguides, two or more mirrors formed on a substrate, thermal actuators supporting at least one of the mirrors, wherein one of the mirrors is actuated by thermal expansion of the actuator. Because all mirrors are formed on a substrate, a manufacturing process is simple and an initial resonance wavelength can be precisely adjusted. Since the thermal expansion is generated by the electrical current directly flowing through the thermal actuators, it can be actuated by a low consumption power. Also, since an electrostatic force is not used to move the mirrors, a sticking phenomenon between the mirrors does not occur, and the wavelength can be tunable in a wide range.

Abstract: The present invention relates to a sound transmission system using a human body as a propagation medium. The transmission system includes a first signal transmitter and a second signal transmitter respectively generating signals having frequencies corresponding to each other, the first and second signal transmitters being coupled to the human body, wherein the first and second signal transmitters respectively generate high frequency signals having an opposite phase to each other, and the respective signal transmitters combine the audio signals and the high frequency signals to transmit the combined signals to the human body. The respective signal transmitters combine the generated audio signals and high frequency signals, adjust an output phase of the combined signals, and transmit the combined signals through the human body.

Abstract: A method for the preparation of N-pyrazolylamidoximes of the general formula I R1 and R2 independently represent an alkyl, aryl, or heteroaryl group, comprises reacting a 5-(?-ketoalkyl)-3-substituted-1,2,4-oxadiazoles of the general formula II with hydrazine.

Abstract: An oxadiazole compound and process of making same, is represented by Formula I: wherein R1 represents a substituted or unsubstituted straight, branched, or cyclo-alkyl group having at least two carbon atoms, and R2 represents an alkyl, aryl, or heteroaryl group.

Abstract: An active type tunable wavelength optical filter having a Fabry-Perot structure is disclosed. A tunable wavelength optical filter which comprises a lower mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion; an upper mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion and which is spaced away from the lower mirror by a predetermined distance; a connecting means for connecting and supporting the lower mirror and the upper mirror to a semiconductor substrate; and electrode pads for controlling the gap between the lower mirror and the upper mirror by an electrostatic force and the method of manufacturing the same are provided.

Abstract: The present invention relates to human insulin expression plasmids and a method for producing insulin using the same. The plasmids comprise a sequence encoding a compound of the formula R—B—X-A, in which R is a leader peptide of the formula of Met-Thr-Met-Ile-Thr-Y (SEQ ID NO: 36), in which Y is one selected from lysine, arginine, a peptide containing lysine as an amino acid at its C-terminal, or a peptide containing arginine as an amino acid at its C-terminal; B is human insulin B-chain or analogue thereof; X is a peptide connecting B with A; and A is human insulin A-chain or analogue thereof. The method for preparing insulin using the plasmids according to the present invention converts the proinsulin fusion protein into human insulin in a single enzymatic cleavage process and minimizes the generation of by-products after the enzymatic cleavage, thereby producing insulin at a high yield.

Abstract: A variable optical attenuator with tunable wavelength selectivity includes at least two reflectors disposed parallel to each other at a predetermined angle from an optic axis and driving units connected to said at least two reflectors for allowing the reflectors to move back and forth in a direction perpendicular or parallel to the optic axis or to revolve centering on an axis perpendicular or parallel to the optic axis. Since the variable optical attenuator of the present invention serves as a variable optical attenuator and, at the same time, as a tunable wavelength filter, problems of insertion loss and optical alignment that might be caused by separately installing a variable optical attenuator and a wavelength filter can be effectively prevented. Moreover, by implementing the variable optical attenuator and the tunable wavelength filter by using a single device, the size of a system using the optical attenuator can be reduced.

Abstract: A variable optical attenuator with tunable wavelength selectivity includes at least two reflectors disposed parallel to each other at a predetermined angle from an optic axis and driving units connected to said at least two reflectors for allowing the reflectors to move back and forth in a direction perpendicular or parallel to the optic axis or to revolve centering on an axis perpendicular or parallel to the optic axis. Since the variable optical attenuator of the present invention serves as a variable optical attenuator and, at the same time, as a tunable wavelength filter, problems of insertion loss and optical alignment that might be caused by separately installing a variable optical attenuator and a wavelength filter can be effectively prevented. Moreover, by implementing the variable optical attenuator and the tunable wavelength filter by using a single device, the size of a system using the optical attenuator can be reduced.

Abstract: Disclosed are a method and an apparatus for producing a uranium foil with fine crystalline granules by forming the foil by the gravitational dropping of molten uranium or uranium alloy and rapidly cooling the foil by the contact with cooling rolls, and a foil produced thereby. In accordance with the present invention, a high-purity and high-quality uranium foil with an isotropic structure and fine crystalline granules is easily produced via a simple process without requiring hot rolling and heat treatment processes. The surface of the foil is prevented from oxidizing and residual stress is not imparted to the foil. The productivity and the economic efficiency of the foil are improved.

Abstract: The present invention relates to a wavelength tunable filter capable of being driven such that reflecting mirrors move more distant as well as closer by using the principle a direction of the electromagnetic forces changes depending on the direction of the current flowing perpendicular to the external magnetic field. According to the wavelength tunable filter of the present invention, when it is necessary to have the wavelength tuning range and mechanical structure similar to the conventional wavelength tunable filter driven in only one direction, it is possible to lower the maximum force needed to drive the filter to a half, and reduce a probability that a pill-in phenomenon occurs. On the other hand, it is possible to reduce a wavelength change time of the element by increasing a resonant frequency when the same wavelength tuning ranges are implemented by using the same maximum driving forces.

Abstract: Disclosed are a method and an apparatus for continuously casting a uranium rod so that impurities generated in melting the metallic substance reduced from nuclear spent fuel are easily removed, the molten metal is easily degassed, the oxidation of uranium is prevented, and the molten metal does not remain in a crucible, thereby completely removing the noxious gas, improving the safety of work, allowing the workers to be close to the apparatus, reducing the consumption rate of the inert gas, completely preventing the oxidation of uranium, and being remotely controlled.

Abstract: An active type tunable wavelength optical filter having a Fabry-Perot structure is disclosed. A tunable wavelength optical filter which comprises a lower mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion; an upper mirror in which silicon films and oxide films are sequentially laminated in a multi-layer and the silicon film is laminated on the highest portion and which is spaced away from the lower mirror by a predetermined distance; a connecting means for connecting and supporting the lower mirror and the upper mirror to a semiconductor substrate; and electrode pads for controlling the gap between the lower mirror and the upper mirror by an electrostatic force and the method of manufacturing the same are provided.