Abstract: A method for producing a casting using a gas-permeable casting mold comprising a cavity composed of a production cavity and a flow path, the flow path comprising a sprue through which a gravity-poured melt flows downward, and a runner connecting the production cavity to the sprue, comprising gravity-pouring a metal melt in a volume smaller than that of the entire cavity and larger than that of the production cavity into the gas-permeable casting mold; supplying a gas through the sprue to push the metal melt in the flow path, thereby pushing the metal melt upward in the production cavity, so that the production cavity is filled with the metal melt; in a hypothetical equilibrium state in which a hypothetical liquid fills the production cavity by the supplied gas, setting the volume of the metal melt to be poured to be equal to the volume of the hypothetical liquid, such that the surface height hs of the hypothetical liquid remaining in the flow path after filling the production cavity, the height h1 of the lowe

Abstract: A method for producing a casting using a gas-permeable casting mold comprising a cavity composed of a production cavity and a flow path, the flow path comprising a sprue through which a gravity-poured melt flows downward, and a runner connecting the production cavity to the sprue, comprising gravity-pouring a metal melt in a volume smaller than that of the entire cavity and larger than that of the production cavity into the gas-permeable casting mold; supplying a gas through the sprue to push the metal melt in the flow path, thereby pushing the metal melt upward in the production cavity, so that the production cavity is filled with the metal melt; in a hypothetical equilibrium state in which a hypothetical liquid fills the production cavity by the supplied gas, setting the volume of the metal melt to be poured to be equal to the volume of the hypothetical liquid, such that the surface height hs of the hypothetical liquid remaining in the flow path after filling the production cavity, the height h1 of the lowe

Abstract: A method for producing a casting using a gas-permeable casting mold comprising a cavity composed of a production cavity and a flow path, the flow path comprising a sprue through which a gravity-poured melt flows downward, and a runner connecting the production cavity to the sprue, comprising gravity-pouring a metal melt in a volume smaller than that of the entire cavity and larger than that of the production cavity into the gas-permeable casting mold; supplying a gas through the sprue to push the metal melt in the flow path, thereby pushing the metal melt upward in the production cavity, so that the production cavity is filled with the metal melt; in a hypothetical equilibrium state in which a hypothetical liquid fills the production cavity by the supplied gas, setting the volume of the metal melt to be poured to be equal to the volume of the hypothetical liquid, such that the surface height hs of the hypothetical liquid remaining in the flow path after filling the production cavity, the height h1 of the lowe

Abstract: A method for producing a casting by pouring a metal melt by gravity into a gas-permeable casting mold 1 having a cavity comprising at least a sprue 6, a runner 7 and a product-forming cavity 9, comprising pouring a metal melt into a desired cavity portion 10 including the product-forming cavity through the sprue, the melt being in a volume substantially equal to the volume of the desired cavity portion; supplying a gas 14 to the desired cavity portion through the sprue before the desired cavity portion is filled with the poured melt, so that the melt fills the desired cavity portion; and cooling a portion of the melt in contact with the gas directly or indirectly by water 16 supplied from outside the gas-permeable casting mold, simultaneously with, during or after supplying the gas, thereby solidifying the melt.

Abstract: A method for producing a casting using a gas-permeable casting mold comprising a cavity composed of a production cavity and a flow path, the flow path comprising a sprue through which a gravity-poured melt flows downward, and a runner connecting the production cavity to the sprue, comprising gravity-pouring a metal melt in a volume smaller than that of the entire cavity and larger than that of the production cavity into the gas-permeable casting mold; supplying a gas through the sprue to push the metal melt in the flow path, thereby pushing the metal melt upward in the production cavity, so that the production cavity is filled with the metal melt; in a hypothetical equilibrium state in which a hypothetical liquid fills the production cavity by the supplied gas, setting the volume of the metal melt to be poured to be equal to the volume of the hypothetical liquid, such that the surface height hs of the hypothetical liquid remaining in the flow path after filling the production cavity, the height h1 of the lowe

Abstract: A method for producing a casting by pouring a metal melt by gravity into a gas-permeable casting mold 1 having a cavity comprising at least a sprue 6, a runner 7 and a product-forming cavity 9, comprising pouring a metal melt into a desired cavity portion 10 including the product-forming cavity through the sprue, the melt being in a volume substantially equal to the volume of the desired cavity portion; supplying a gas 14 to the desired cavity portion through the sprue before the desired cavity portion is filled with the poured melt, so that the melt fills the desired cavity portion; and cooling a portion of the melt in contact with the gas directly or indirectly by water 16 supplied from outside the gas-permeable casting mold, simultaneously with, during or after supplying the gas, thereby solidifying the melt.

Abstract: The present invention relates to a container packed with instant food to be cooked by a microwave oven which allows a solid instant food such as instant chow mein and instant macaroni to be reconstituted to its original cooked state with good texture in a short period of time when the food is cooked in a microwave oven without the need to drain water after it is cooked.The container packed with instant food comprises: a container composed of a container body and a lid which is capable of tightly or substantially tightly sealing said container; and a solid instant food accommodated in said container, wherein said food is to be reconstituted and made ready for eating on absorbing water when said container packed with said food is heated in a microwave oven after water is added thereto in an amount equivalent to between 100 and 155 wt % of the water absorption capacity of said food.

Abstract: A directional coupler for coupling two single-polarization optical fibers each comprising a core, a cladding, and an elliptic jacket having a major axis is made by preparing two quartz substrates each of which is formed with a channel on one major surface; embedding and bonding the jacketed single-polarization optical fibers in the channels in the substrates, respectively, such that the major axis of the elliptic jacket extends perpendicular to the substrate surface; abrading away the substrates together with the fiber embedded therein from the major surface to a depth where light traveling in the core of said fiber may leak out; placing one substrate on the other substrate with the abraded surfaces facing each other; and bonding the substrates to keep the cores in sufficiently close relation to establish evanescent wave coupling therebetween. A stress perpendicular to the major axis is preferably applied to the fiber.

Abstract: An optical branching element mainly composed of a central linear optical transmission line and a plurality of peripheral linear optical transmission lines. They have circular sections of approximately the same diameters. The peripheral linear optical transmission lines are provided around the central linear optical transmission line such that their end surfaces are arranged on the same plane as the end surface of the central linear optical transmission line. A holder fixes these central and peripheral linear optical transmission lines on the end surface side. Semispheric reflecting concave surfaces having radii larger than the diameters of said peripheral linear optical transmission lines are formed around the contact points of the end surface of the central linear optical transmission line and the end surfaces of the linear optical transmission lines.

Abstract: An optical wavelength demultiplexer includes a retainer means which curvedly retains an optical fiber. A mirror-polished surface is formed on the convex side of a curved portion of the optical fiber which is retained by the retainer means in such a manner that the mirror-polished surface is in close proximity to the core of the optical fiber. Further, a diffraction grating is disposed such as to oppose and contact the mirror-polished surface. The pitch of the diffraction grating is set to be .lambda./2n.sub.f, where .lambda. represents the wavelength of light to be separated, and n.sub.f the effective refractive index of the optical fiber. The direction of the pitch is selected to be coincident with the extending direction of the optical fiber.

Abstract: In an optical fiber system comprising first and second polarization-maintaining fibers, a first orthogonal coordinate system of the first polarization-maintaining fiber is azimuthally rotated relative to a second orthogonal coordinate system of the second polarization-maintaining fiber by the use of an optical coupler by a preselected angle between 0.degree. and 90.degree., both exclusive. Preferably, the optical coupler is shorter than a beat length of each fiber and the preselected angle is equal to 45.degree.. The optical fiber system is applicable to an optical sensor for sensing a variable physical parameter. In the sensor, a light beam is incident onto one end of the first polarization-maintaining fiber so that a plane of polarization of the light beam is matched to one of those planes of the first polarization-maintaining fiber which are determined by the first orthogonal coordinate system.

Abstract: A method for producing dried instant noodles containing less than 15% moisture as a final product. It is characterized by dehydrating raw noodles containing 35-45% moisture using super-heated steam and adjusting evaporation of water from the noodles at the rate of 0.25-1.00 g/second per 100 g of the raw noodles.

Abstract: The optical reflective filter is made from a photosensitive optical fiber having a cladding and a core including germanium. Refractive index perturbations are light induced in the fiber in the region of the guided light. The perturbations can be made to have a constant or a varying periodicity, or a series of constant periodicities. The filters are made from single mode or low order mode fibers having germanium doped silica or germania cores. The center frequency for reflective band or bands has a wavelength in the 400 nm to 550 nm range. The reflective band or bands in the filter can be shifted by stretching the filter.