Abstract: A method for manufacturing a nitride semiconductor device includes the steps of growing a GaN channel layer on an SiC substrate using a vertical MOCVD furnace set at a first temperature using H2 as a carrier gas, and TMG and NH3 as raw materials, holding the SiC substrate having the grown GaN channel layer in the MOCVD furnace set at a second temperature higher than the first temperature using H2 as a carrier gas, the MOCVD furnace being supplied with NH3, and growing an InAlN layer on the GaN channel layer using the MOCVD furnace set at a third temperature lower than the first temperature using N2 as a carrier gas, and TMI, TMA, and NH3 as raw materials.

Abstract: A method of controlling an optical modulator having a first child modulator, a second child modulator, and a parent modulator includes applying a first bias, on which a first dither signal with frequency f1 is superimposed, to the first child modulator, applying a second bias, on which a second dither signal with frequency f2 different from f1 is superimposed, to the second child modulator, applying a third bias, on which a third dither signal with frequency f3 different from both f1 and f2 is superimposed, to the parent modulator. A first error component having the f1 frequency, and a second error component having a beat frequency of f2 and f3 frequencies are detected from the output light from the optical modulator, and a first error signal is generated from the first error component and the second error component to adjust the first bias.

Abstract: A control device includes: an in-vehicle communication unit capable of communicating with an on-vehicle control device; and a control unit configured to control the in-vehicle communication unit. The control unit monitors a power storage amount of an on-vehicle battery during traveling, and executes a charge control for causing the in-vehicle communication unit to transmit an instruction of power generation to an on-vehicle generator that supplies power to the on-vehicle battery, when the power storage amount is reduced to reach a threshold value. The threshold value corresponds to a power amount greater than a necessary power amount required for an update process of a control program in the on-vehicle control device.

Abstract: There is provided a method of manufacturing an optical connector, including: preparing a multi-core optical fiber including a glass fiber and a resin coating that covers the glass fiber; inserting the glass fiber exposed from the resin coating into the ferrule such that the glass fiber protrudes from an end surface of a ferrule by a length A; rotating and aligning the multi-core optical fiber with respect to the ferrule; fixing the multi-core optical fiber to the ferrule; and so as to scrap off a tip end of the ferrule by a length. A deviation angle in the circumferential direction between a first initial end surface of the one end of the prepared glass fiber and a cross section of the glass fiber separated from the initial end surface by a length A+B mm is equal to or less than 0.9°.

Abstract: The information providing system includes a mobile terminal and a server device that communicates with the mobile terminal. The mobile terminal includes: a sensor that reads a facility ID used to identify at least one facility; and a communication device that transmits, to the server device, the facility ID read by the sensor and a user ID used to identify a user of the mobile terminal. The server device includes: a memory that stores a plurality of types of facility-related information; a processor that extracts, from the plurality of types of facility-related information stored in the memory, facility-related information corresponding to the facility ID and the user ID transmitted from the mobile terminal; and a communication device that transmits, to the mobile terminal, the facility-related information extracted by the processor. The mobile terminal includes a display on which the facility-related information transmitted from the server device is displayed.

Abstract: The aluminum alloy in the cross-section of the surface layer region of the aluminum alloy plate contains a compound containing one or more elements selected from the group consisting of silicon, magnesium, iron, copper, manganese, chromium, zinc, zirconium, and titanium, and aluminum. The number of fields of view containing the compound having an equivalent circle diameter of 5 ?m or more out of 10 fields of view extracted from the cross-section is 3 or less. In the cross-section, the number density of the compound having an equivalent circle diameter of 1.5 ?m or more and less than 5.0 ?m is 0.0010 per ?m2 or less, and the area ratio of the compound having an equivalent circle diameter of 0.5 ?m or more is 0.1% or more and less than 1.0%.

Abstract: A polarization-maintaining optical fiber includes at least one polarization maintaining core, a first cladding surrounding the at least one polarization maintaining core, and a second cladding surrounding the first cladding. The at least one polarization maintaining core includes a core and a pair of low-refractive-index portions each having a refractive index lower than a refractive index of the core. In a cross section, at least a portion of an outer periphery of each of the pair of low-refractive-index portions is in contact with the core, and an outer periphery of the core, excluding portions each being in contact with the low-refractive-index portions, has a circular shape. A maximum value of an absolute value of a residual stress in the cross section is 100 MPa or less. A mode-field flattening f is 0.05 to 0.40 at any wavelength within a range of 850 nm to 1625 nm.

Abstract: A ferrule according to an embodiment is a ferrule of an optical connector to which a counterpart connector is connected. The ferrule includes an end portion having an optical fiber retention hole and a guide hole opened, the optical fiber retention hole into and on which a fiber is inserted and retained, the guide hole into which a guide pin is inserted, the guide pin establishing positioning to the counterpart connector. The end portion includes an optical surface including an opening of the optical fiber retention hole, a guide hole exposure surface including an opening of the guide hole, and a step part formed between the optical surface and the guide hole exposure surface.

Abstract: An indium phosphide single crystal including a straight body portion having a cylindrical shape, wherein a residual strain in a tangential direction in an outer circumferential portion is a compressive strain, the outer circumferential portion extending between an inner circumferential surface located 10 mm inward from an outer circumferential surface of the straight body portion toward a central axis and a location located 5 mm inward from the outer circumferential surface. There is also provided an indium phosphide single crystal substrate, wherein a residual strain in a tangential direction in an outer circumferential portion is a compressive strain, the outer circumferential portion extending between an inner circumference located 10 mm inward from an outer circumference toward a center and a location located 5 mm inward from the outer circumference.

Abstract: The optical fiber comprises a glass fiber comprising a core and a cladding, a primary resin layer in contact with the glass fiber and covering the glass fiber, and a secondary resin layer covering the primary resin layer, wherein the primary resin layer contains a cured product of a resin composition containing a urethane (meth)acrylate oligomer, a monomer, a photopolymerization initiator and an aromatic acid compound, a content of the aromatic acid compound is 20 ppm or more and 12000 ppm or less based on a total amount of the resin composition, and Young's modulus of the primary resin layer is 0.6 MPa or less at 23° C.±2° C.

Abstract: An optical fiber connection structure includes: a tubular member; a first collimator attached to a first end of the tubular member in an axial direction; and a second collimator attached to a second end of the tubular member. The first collimator includes a first optical fiber, a first ferrule, a first lens, and a first sleeve. The second collimator includes a second optical fiber, a second ferrule terminating the second optical fiber, a second lens, and a second sleeve. The first sleeve is fixed to the first end via adhesive in a state where the first lens faces the tubular member, and the second sleeve is fixed to the second end via adhesive in a state where the second lens faces the tubular member. An outer diameter of the second ferrule is larger than that of the second lens.

Abstract: An optical module according to an embodiment includes a first optical component and a second optical component including a multicore fiber (MCF) and a spatial joining part. The first optical component includes a first uncoupled MCF having small optical coupling between cores and a first coupled MCF having a mode field diameter (MFD) larger than a MFD of the first uncoupled MCF. The second optical component includes a second uncoupled MCF having small optical coupling between cores and a second coupled MCF having a MFD larger than a MFD of the second uncoupled MCF. In the first coupled MCF and the second coupled MCF, crosstalk is periodically produced along the length direction of an MCF, and the total of the length of the first coupled MCF and the length of the second coupled MCF is a length L in which crosstalk is suppressed.

Abstract: A wireless sensor system is provided with: a wireless terminal device which is driven by electric power stored in a power storage unit and transmits measurement information indicating a result of measurement by a sensor; and a management device which receives the measurement information transmitted from the wireless terminal device.

Abstract: An optical module includes a base member including a first surface, a first semiconductor light-emitting element mounted on the first surface and configured to emit first light having a first wavelength, a first filter mounted on the first surface and including a first reflection surface configured to reflect the first light, a second semiconductor light-emitting element mounted on the first surface and configured to emit second light having a second wavelength differing from the first wavelength, and a second filter mounted on the first surface and including a second reflection surface configured to reflect the second light.

Abstract: A method of making a sintered part includes a step of applying a machining process to a compacted part with a tool to make a machined compacted part having a cogwheel shape, and a step of sintering the machined compacted part to make a sintered part, wherein the machining process is such that a surface of the compacted part on a side where the tool exits is supported by a plate member having a tooth pattern with same specifications as a tooth pattern of the cogwheel shape, and the tool is used to machine portions of the compacted part corresponding to tooth spaces of the plate member.

Abstract: This stator core is a stator core for a rotating electric machine of an axial gap type and includes a body portion formed by a compaction-molded body of soft magnetic powder whose surfaces are coated with insulating films, wherein the body portion is provided with one or a plurality of through holes.

Abstract: The resin composition according to an aspect of the present disclosure is a resin composition containing a photopolymerizable compound comprising urethane (meth)acrylate and a polyrotaxane, and a photopolymerization initiator, and the content of the polyrotaxane is 0.05% by mass or more and 11% by mass or less based on the total amount of the photopolymerizable compound.

Abstract: A composite sintered material includes: a plurality of diamond grains having an average grain size of less than or equal to 10 ?m; a plurality of cubic boron nitride grains having an average grain size of less than or equal to 2 ?m; and a plurality of aluminum oxide grains having an average grain size of less than or equal to 0.5 ?m; and a remainder of a binder phase, wherein at least parts of adjacent diamond grains are bound to one another, the binder phase includes cobalt, in the composite sintered material, a content of the diamond grains is from 30 to 92 volume %, a content of the cubic boron nitride grains is from 3 to 40 volume %, a content of the aluminum oxide grains is from 2 to 15 volume %, and a content of the cobalt is from 3 to 30 volume %.

Abstract: A power conversion device includes a multilayer board including conductive layers that form a primary-side coil and a secondary-side coil of a transformer; and a circuit board electrically connected to the multilayer board, having a first conversion circuit formed therein or thereon. The multilayer board includes a transformer region in which the transformer is formed; a core member disposed in the transformer region and around the primary-side coil and secondary-side coil are wound; a circuit formed region which is adjacent to the transformer region and a second conversion circuit is formed, the second conversion circuit being electrically connected to the primary-side coil or the secondary-side coil; and a terminal portion which is electrically connected to the secondary-side coil or the primary-side coil. The first conversion circuit is electrically connected to the transformer via the terminal portion. One of the coils has a smaller number of turns than the other coil.

Abstract: The installation angle of a radar for traffic monitoring can be easily adjusted. A radar installation-angle adjustment method is a radar installation-angle adjustment method of adjusting an installation angle of an infrastructure radio-wave radar configured to detect an object in a target area. The method includes first adjustment of adjusting an angle of a radar installed at an installation target without operating the radar; and second adjustment of operating the radar the angle of which has been adjusted in the first adjustment, and adjusting the angle of the radar based on a detection result of the radar.