Abstract: A radio frequency antenna measurement system (10) of the present invention includes a receiving antenna (14) that receives a radiated radio wave from an on-chip radio frequency antenna (AUT). The receiving antenna (14) includes a waveguide (14A) in which a connector (14B) for outputting a reception signal to the power sensor (15) is integrally formed at a rear end. Accordingly, in a state where a microscope (MS) necessary for position adjustment of a feed probe (12) is installed, it is possible to construct a reception system that receives the radiated radio wave from the AUT and measures a radiation characteristic on a stage (11), and to measure the radiation characteristic such as a gain and radiation pattern of the AUT with high accuracy.

Abstract: A heat exchanger includes tubes arranged side by side, and a tank connected to ends of the tubes. The heat exchanger performs heat exchange between a first fluid flowing inside the tubes and a second fluid flowing outside the tubes. The heat exchanger includes a closing member disposed inside the tank and partially closing an opening provided at an end of a predetermined tube that is at least one of the tubes. The predetermined tube has a protrusion formed at the end of the predetermined tube. The closing member has an avoiding structure that avoids interference between the protrusion and the closing member.

Abstract: A heat exchanger includes tubes, a tank, and a prevention plate arranged inside the tank and contacting end surfaces of the tubes to prevent heat medium from flowing into the tubes in a certain region. Flow paths are formed in each tube and arranged in a width direction of the tube. The prevention plate includes a deformable portion elastically deformable by contacting an edge of the opening at a time of inserting the prevention plate into the tank from the opening. The deformable portion of the prevention plate that has been inserted into the tank is restored and receives a reaction force from an inner surface of the tank such that the prevention plate is shifted along the width direction by the reaction force.

Abstract: The present invention relates to a method for operating a separation membrane in which a liquid-to-be-filtrated is subjected to filtration to obtain a filtrate, the method including: an accumulated amount calculation step of calculating an amount of constituent components of the liquid-to-be-filtrated accumulated on a surface and in pores of the separation membrane after setting an initial value; a chemical liquid cleaning effect calculation step of calculating a restoration degree of an accumulated amount of the constituent components or membrane filtration resistance in chemical liquid cleaning based on a result of accumulated amount calculation; and a chemical liquid cleaning condition determination step of determining a chemical liquid cleaning condition based on results obtained in the accumulated amount calculation step and the chemical liquid cleaning effect calculation step.

Abstract: Arranged on a surface of a substrate are a patch conductor that radiates an electromagnetic field having been fed, a feed line that feeds the patch conductor with the electromagnetic field having been input, two slits parallel to the feed line on both sides of a connection part of the feed line toward an inner side of the patch conductor, and a ring conductor at a space from the patch conductor with an interposition of a gap to surround an outer periphery of the patch conductor. Accordingly, an electric capacitance can be formed between the patch conductor and the ring conductor, and when achieving impedance matching with the feed line, adjustment can be performed using the size of the ring conductor and the gap.

Abstract: The present invention provides a method for preparing a water quality profile that has (1) a step 1 for supplying water to be treated to a separation membrane module with a supply port for the water being treated and multiple permeate outlets and obtaining permeate, (2) a step 2 for varying the ratio of the flow rates of the respective permeates flowing out of the multiple permeate outlets, (3) a step 3 after step 2 for measuring the respective water qualities of the permeates, and (4) a step 4 for plotting the relationship between the ratio of the respective permeate flow rates varied in step 2 and the respective water qualities of the permeates measured in step 3 as a scatter diagram, steps 2-4 being repeated multiple times.

Abstract: A beamformer includes a waveguide through which an electromagnetic wave is transmitted, a phase shifter placed in the waveguide, and a bias chip electrically connected to the phase shifter, the phase shifter includes a metamaterial cell having a capacitive element on a dielectric substrate, and the bias chip applies a voltage to the metamaterial cell, thereby changing a capacitance of the capacitive element and a phase of the electromagnetic wave.

Abstract: Stub conductors are disposed so as to surround an outer periphery of a patch conductor and be spaced from the patch conductor with a gap positioned between the stub conductors and the patch conductor.

Abstract: An embodiment is a mixer circuit including a power divider that divides an LO signal with equal amplitude and equal phase, delay circuits, unit mixers, transmission lines, and a power combiner that combines, with equal amplitude and equal phase, RF signals output from the unit mixers. A phase delay amount of the LO signal by the k-th delay circuit from an IF port side is set to ?1?k??IF or ?1+k??IF, where ??IF is a phase delay amount with respect to an IF signal of each of the transmission lines.

Abstract: A permittivity measuring method includes measuring a set of phases at sampling frequencies of at least three points in each of a first-half portion and a second-half portion of a phase characteristic of electromagnetic waves that passed through a measurement target, if the mode of the phase changes of both sets of phases belongs to a phase group in which change of the at least three points in the first half and change of at least three points in the second half are both monotonic change, maximal values, or minimal values, calculating the permittivity using the phase slope of the phases in the first-half portion and the phases in the second-half portion, and if the mode of the phase changes does not belong to the phase group, calculating the permittivity by fitting the phases of either the first half or the second half to a quadratic function.

Abstract: A semiconductor photodetector includes a substrate; a mesa structure on the substrate, the mesa structure being composed of some layers including an upper layer and a lower layer, the upper layer being an absorption layer of light, the lower layer being a wide bandgap layer with a bandgap wide enough not to absorb the light; and an insulating film covering a side of the mesa structure, each of the layers comprising single crystals of III-V semiconductors and having a top of a (100) plane, the top of the wide bandgap layer having a shape including a pair of vertices, in [0-11] and [01-1] directions, on a circumference of a minimum bounding circle.

Abstract: A gain adjustment unit constituted by a distribution switch having a control terminal is provided in an input unit of an amplifier circuit. One end of a coupler is connected to an output line of the amplifier circuit, another end of the coupler is connected to an anode of a diode, and a monitor terminal is connected via a low-pass filter to a cathode of the diode. The anode of the diode is unbiased.

Abstract: An embodiment differential amplifier circuit includes an amplifier section including differential pair transistors to which a differential signal is input and a tail current circuit made up of a short stub provided between a ground terminal of the amplifier section and a ground. In an embodiment, an electrical length of the short stub is shorter than a quarter wavelength of an operation frequency of the differential amplifier circuit.

Abstract: A semiconductor light-receiving element, includes: a semiconductor substrate; a high-concentration layer of a first conductivity type formed on the semiconductor substrate; a low-concentration layer of the first conductivity type formed on the high-concentration layer of the first conductivity type and in contact with the high-concentration layer of the first conductivity type; a low-concentration layer of a second conductivity type configured to form a PN junction interface together with the low-concentration layer of the first conductivity type; and a high-concentration layer of the second conductivity type formed on the low-concentration layer of the second conductivity type and in contact with the low-concentration layer of the second conductivity type. The low-concentration layers have a carrier concentration of less than 1×1016/cm3. The high-concentration layers have a carrier concentration of 1×1017/cm3 or more.

Abstract: In an embodiment, an edge extraction method includes: emitting, toward an object, an electromagnetic wave polarized only in one direction perpendicular to a propagation direction; receiving a transmitted electromagnetic wave that has been transmitted through the object, using a receiving antenna; calculating an intensity in the propagation direction of the transmitted electromagnetic wave based on an intensity of the transmitted electromagnetic wave received by the receiving antenna; and obtaining a spatial distribution of the intensity in the propagation direction of the transmitted electromagnetic wave.

Abstract: A vehicle monitor apparatus including a vehicle monitor apparatus, including a main bracket supported by a pair of front and rear frames extending in a left-right direction on a ceiling portion of a vehicle, a monitor attached to the main bracket, and a sub-bracket interposed between the main bracket and a target frame, the target frame being at least one of the pair of front and rear frames. The sub-bracket includes a first fixing portion fixed to the target frame and a second fixing portion fixed to the main bracket, and at least one of the first fixing portion and the second fixing portion includes a height adjustment mechanism configured so that a height of the main bracket relative to the target frame is adjustable.

Abstract: A semiconductor photodetector includes: a substrate; a light-receiving mesa structure, on a first surface of the substrate, including semiconductor layers that includes an absorption layer; an insulating film overlapping with the light-receiving mesa structure in a transverse direction, the insulating film surrounding a side surface of the light-receiving mesa structure; a first electrode, on the first surface, including a mesa electrode electrically connected to and in contact with a top surface of a top layer of the semiconductor layers, the first electrode including a protruding electrode on the insulating film, the protruding electrode being electrically continuous to the mesa electrode, extending outward, and overlapping with the light-receiving mesa structure in the transverse direction, the protruding electrode being smaller in width than the mesa electrode; and a second electrode, on the first surface, electrically connected to a bottom surface of a bottom layer of the semiconductor layers.

Abstract: A patch conductor has a hexagonal shape as a whole in a plan view in which both corners of one side of a rectangle are obliquely cut off, and a connection portion located at a center of the side is connected to a feed line. In this way, an inclined portion inclined with respect to a direction X is formed between the side and a side of the patch conductor, and an inclined portion inclined with respect to the direction X is formed between the side and a side. This makes it possible to significantly improve directivity and gain and obtain a wideband radiation characteristic.

Abstract: A radio frequency antenna measurement system (10) of the present invention includes a receiving antenna (14) that receives a radiated radio wave from an on-chip radio frequency antenna (AUT). The receiving antenna (14) includes a waveguide (14A) in which a connector (14B) for outputting a reception signal to the power sensor (15) is integrally formed at a rear end. Accordingly, in a state where a microscope (MS) necessary for position adjustment of a feed probe (12) is installed, it is possible to construct a reception system that receives the radiated radio wave from the AUT and measures a radiation characteristic on a stage (11), and to measure the radiation characteristic such as a gain and radiation pattern of the AUT with high accuracy.

Abstract: A plurality of waveguide structures are loaded on a top surface opposed to a bottom surface of a metal case, on which a high-frequency circuit is mounted, a height, a width, and a length of each of the plurality of waveguide structures have dimensions corresponding to a quarter-wave of a cutoff frequency indicating a frequency band of a target electromagnetic wave to be blocked, and a width and a length of each of the plurality of waveguide structures have dimensions that allow only a high-frequency wave of a mode to propagate in the frequency band.