Publisher Summary Thermal control of electronic components has one principal objective, to maintain relatively constant component temperature equal to or below the manufacturer's maximum specified service temperature, typically between 85 and 100°C. It is noted that even a single component operating 10°C beyond this temperature can reduce the reliability of certain systems by as much as 50%. Therefore, it is important for the new thermal control schemes to be capable of eliminating hot spots within the electronic devices, removing heat from these devices and dissipating this heat to the surrounding environment. Several strategies have developed over the years for controlling and removing the heat generated in multichip modules, which include advanced air-cooling schemes, direct cooling, and miniature thermosyphons or free-falling liquid films. The chapter summarizes analytical, numerical, and experimental work in literature, in order to facilitate the improvement of existing schemes and provide a basis for the development of new ones. The chapter focuses on investigations performed over the past decade and includes information on the thermal control of semiconductor devices, modules, and total systems.

Thermal Control of Electronic Equipment and Devices

An X-ray CT apparatus comprises: motion information acquisition means that acquires periodical motion information on a motion portion of an object to be examined; a detector that rotates together with an X-ray source and detects X-rays applied to the object from the X-ray source to acquire projection data per collection region; and reconstruction means that processes the projection data resulting from the detector to reconstruct a tomogram of the object, wherein the X-ray CT apparatus further includes delay time determination means that determines a delay time by adding a time width of the collection region and a processing delay time in the X-ray CT apparatus and a time interval from the moment when the phase of the measured periodical motion information is matched with the phase of the rotation period of the X-ray CT apparatus to the moment when they are matched next time, and collection means that correlates, with the periodical motion information obtained by the motion information acquisition means, and successively collects the projection data obtained from the detector, with the reconstruction means starting reconstruction of the tomogram after the delay time.

X-ray ct device

A system for restricting mixing of air in a data center includes a plurality of racks, each of the racks having a front face and a back face The system includes an enclosure for collecting air released from the back faces of the plurality of racks, the enclosure configured to substantially contain the air in an area between the first row and the second row and having a roof panel coupled to the first row of racks and the second row of racks configured to span a distance between the first row of racks and the second row of racks The enclosure is configured to maintain a first air pressure inside of the enclosure that is substantially equal to a second air pressure outside the enclosure

Data center cooling

An imaging apparatus and related method comprising a detector located a distance from a source and positioned to receive a beam of radiation in a trajectory; a detector positioner that translates the detector to an alternate position in a direction that is substantially normal to the trajectory; and a beam positioner that alters the trajectory of the radiation beam to direct the beam onto the detector located at the alternate position

Systems and methods for imaging large field-of-view objects

A modular door mounted heat exchanger (10) for use with an outdoor equipment enclosure (12) of the type having a sealed equipment compartment (22) used to house heat generating electronics and telecommunications equipment (29) therein is disclosed. The heat exchanger includes a door panel (33) sized and shaped to be received on, and to close an access opening (20) defined as a part of the equipment enclosure. The door panel has an interior surface (34) for facing inwardly of the enclosure, and an exterior surface (36) for facing outwardly of the enclosure. A heat exchanger cover (37) constructed and arranged to be mounted to the exterior surface of the door panel is provided. The heat exchanger cover defines a plenum (38) between the exterior surface of the door panel and the heat exchanger cover. At least a first opening (40) and at least a spaced second opening (41) are defined within the plenum for defining an air flow path (44, 45) passing within and at least partially along the plenum. At least one fan (42, 48, 79) is provided for drawing air into and exhausting air out of the plenum through the at least first and second openings, respectively. The fan is constructed and arranged to draw outside air through the plenum for cooling the exterior surface of the door panel, so that the air within the enclosure that comes into contact with the interior surface of the door panel is in turn cooled.

Door mounted heat exchanger for outdoor equipment enclosure

A thermal conductivity sheet is provided which is superior all in heat radiating characteristics (thermal conductivity) in the direction of sheet thickness, close-contact with respect to parts to be cooled, and electrical insulation. In a thermal conductivity sheet 1 in which a plurality of highly thermally conductive insulators 3 are dispersed in a matrix insulator 2, the highly thermally conductive insulators 3 are oriented obliquely or erectly in the direction of thickness of the thermal conductivity sheet 1 such that at least one end faces of the highly thermally conductive insulators 3 are exposed to a surface of the matrix insulator 2. Preferably, a ratio of the total sectional area of the highly thermally conductive insulators 3 to the total surface area of the thermal conductivity sheet 1 is set to be equal to or larger than 1%.

Thermal conductivity sheet

A radiation detector of this invention includes a scintillator for converting an X-ray incident from a surface side into light, at least one photodiode chip having a plurality of photodiodes for converting the converted light into electrical signals, at least one switching chip having a plurality of switching elements for reading out a plurality of signals from the plurality of photodiodes, and at least one data acquisition chip having a plurality of data acquisition systems for amplifying the plurality of readout signals and converting the signals into digital signals. The photodiode chip, the switching chip, and the data acquisition chip are commonly mounted on a rigid multilayer wiring board.

Radiation detector, radiation detecting system and X-ray CT apparatus

A cooling apparatus for a housing which is provided with an opening at the upper part thereof, comprises a casing located on the upper part of the housing and including a bottom plate to close the opening and a chamber, a partition wall provided in the casing to divide the chamber into a first chamber section and a second chamber section, heat exchanger including at least one heat pipe provided in the casing through the partition wall with coolant therein for exchanging heat in the first chamber section with heat in the second chamber section. The heat pipe has one end portion in the first chamber section and the other end portion in the second chamber section, and inclines with the one end portion located lower than the other end portion.

Cooling apparatus for a closed housing

PROBLEM TO BE SOLVED: To provide a radiation detector, a radiation detecting system and an X-ray CT system in which the number of arrays can be increased. SOLUTION: The radiation detector has a scintillator 9 for converting incident X-rays from the surface side into light, a photodiode chip 2 having a photodiode 3 for converting the light thus converted into an electrical signal, a switching chip 4 having a transistor 5 for reading out a signal from the photodiode 3, and a data collecting chip 8 for amplifying and digitizing a signal thus read out, and the photodiode chip 2, the switching chip 4 and the data collecting chip 8 are mounted commonly on a rigid multilayer wiring board 30.

Radiation detector, radiation detecting system, x-ray ct system

A semiconductor switching apparatus includes a member for radiating heat generated from semiconductor switching element chips and for reducing a thermal stress. The lengths of gate electrode wires are equally set. The semiconductor switching apparatus has a large capacity and good switching characteristics.

Tomiya Sasaki

Papers

Thermal conductivity sheet

Radiation detector, radiation detecting system and X-ray CT apparatus

Cooling apparatus for a closed housing

Radiation detector, radiation detecting system, x-ray ct system

Power semiconductor switching apparatus with heat sinks