Abstract: A chromatic dispersion distribution measurement apparatus, comprises: a chromatic dispersion value calculation unit for calculating a plurality of actual chromatic dispersion values in an optical device at a plurality of wavelengths; and a chromatic dispersion interpolation unit for interpolating an expected chromatic dispersion value between the actual chromatic dispersion values calculated by the chromatic dispersion value calculation unit, in order to obtain a chromatic dispersion distribution as a function of wavelength.

Abstract: A chromatic dispersion distribution measurement apparatus, comprises: a portion information obtaining unit for obtaining a portion information which specifies a portion of an optical device to be measured; a sign information obtaining unit for obtaining a sign information which indicates a correct sign to be marked on a chromatic dispersion value in the specified portion; and a sign converting unit for converting an initial sign marked on the chromatic dispersion value in the specified portion, into the correct sign in accordance with the sign information obtained by the sign information obtaining unit.

Abstract: A chromatic dispersion distribution measurement apparatus, comprises: an output light intensity measurement unit for measuring an intensity of an output light outputted from an optical device to be measured; and an input light intensity control unit for automatically controlling an intensity of an input light to be inputted into the optical device to be measured, in accordance with the intensity of the output light, which is measured by the light intensity measurement unit.

Abstract: An optical fiber chromatic dispersion distribution measuring apparatus for measuring the chromatic dispersion distribution of an optical fiber under test comprising two light sources 1, 2 at least one of which can change wavelength thereof, wherein light beams having different wavelengths from each other and emitted from the two light sources are inputted to the optical fiber under test 7 to measure a four-wave mixing light beam generated by interaction between the two light beams by optical time domain reflectometer (OTDR) 9; wherein an optical bandpass filter 8 having a fixed center wavelength is provided at a previous stage of the optical time domain reflectometer (OTDR); and wherein a coherence controller 10 for controlling coherence of at least one of the light beams outputted from the two light sources 1, 2.

Abstract: An apparatus for measuring the chromatic dispersion profile of an optical fiber using two light sources 1 and 2 at least one of which is tunable in wavelength, in which two light beams of different wavelengths from said two light sources are injected into a optical fiber under test 7 and the four-wave mixing light that is generated by interaction between said light beams of different wavelengths is measured with an optical time domain reflectometer (OTDR) 9, characterized in that an optical bandpass filter 8 having a fixed central frequency is provided at a stage upstream of said optical time domain reflectometer (OTDR).

Abstract: A disk drive having a buffer memory for storing write data transferred from a host system. The disk drive comprises a CPU and incorporates a disk. In the disk drive, the write data stored in the write buffer area of the buffer memory is written on the disk. The CPU monitors the amount of data accumulated in the write buffer area, while the data is being written on the disk. If the amount of data accumulated in the write buffer area is decreasing, the CPU determines the rate at which the data amount is decreasing. In accordance with the rate determined, the CPU changes the storage size of the write buffer area to a new size. This prevents the write buffer area from becoming empty while data is being read from the write buffer area and being written on the disk, even if the data is transferred from the host system to the disk drive more slowly than the data is transferred from the write buffer area to the disk.

Abstract: A printer and a restoration method for a printing plate which can be reused, while coping with digitization of printing processes is provided. On a substrate serving as a hydrophilic surface mounted beforehand onto a plate cylinder, a toner image portion formed on the surface of a photosensitive material is adhered and fixed directly or via an intermediate body to thereby form an image area. In thus way, the substrate is divided into a hydrophobic image area having at least a 50° or higher contact angle with water and a non-image area having an ink repulsion property, to thereby form a printing plate. After completion of printing, the ink and wetting solution adhered to the surface of the printing plate are cleaned by a cleaning apparatus, and image area on the surface of the printing plate is then removed by a chemical treatment solution supply roller, to thereby restore the printing plate to the initial condition so that this can be reused.

Abstract: The outer surface of an article is covered with a wrapping film, and both edges of the film are lap-welded with each other to constitute a body seal section. Both of the upper and lower edges of the film overlap extending out of an article to be wrapped are folded to the inside of the article, whereby upper and lower folded parts are formed. These folded parts overlap with each other, and are bonded and lap-welded together, thereby constituting a side seal section. An unbonded part is formed along the periphery of the upper folded part, wherein the upper folded part and the lower folded part are not bonded together. Two slits are formed in that unbonded part substantially at right angles or an inclined angle to the edge of the upper folded part, and spaced apart from each other by a certain interval. When an interval between the slits is peeled off with a finger, the unbonded part splits along the slits, and hence the side seal section splits.

Abstract: Novel pyrimidine compounds of the formula: ##STR1## wherein R.sub.1 and R.sub.1 ' are each hydrogen atom, a lower alkyl, benzyl, an alkali metal, or ammonium; R.sub.2 is hydrogen atom, a halogen atom, a lower alkyl, a lower alkoxy, an aryl, a group of the formula: ##STR2## (wherein R.sub.3 and R.sub.4 are each hydrogen atom, a lower alkyl, or an aryl), or a group of the formula: ##STR3## [wherein R.sub.5 and R.sub.6 are each an alkylene having 1 to 3 carbon atoms, and X is oxygen atom, methylene, or a group of the formula: >N-Y (wherein Y is hydrogen atom, a lower alkyl, benzyl, or an aryl)], which have excellent antiallergic activities and are useful for the prophylaxis and treatment of various allergic diseases, and a pharmaceutical composition containing said pyrimidine compound as an active ingredient.