Abstract:
Method and apparatus for liquefying a gas such as natural gas, utilizing at least one cycle fluid comprising a refrigerating mixture, with at least one first principal cycle fluid under a low pressure in countercurrent heat exchange with the gas which is to be liquefied and with at least one second principal cycle fluid under a high pressure. At least one secondary cycle fluid is obtained by withdrawing a portion in liquid phase from the refrigerating mixture at the high pressure and is expanded to the low pressure and is then added to the first principal cycle fluid. The heat exchange takes place in at least one heat exchanger comprising a stack of plates which form uninterrupted longitudinal compartments forming passages for the first principal cycle fluid under a low pressure, these compartments extending from the cold end of the exchanger, and a plurality of longitudinal compartments forming passages for at least one of the second principal cycle fluid and the fluid to be liquefied, these latter compartments extending to the cold end of the exchanger. The addition of the secondary fluid to the first principal fluid takes place in a distributed manner into each low pressure compartment in at least one transverse volume extending along the thickness of the exchanger, this volume being located at heat exchange distance from the inlets and outlets of the compartments forming passages for the first principal fluid under low pressure.
Abstract:
An apparatus for testing a device. The apparatus comprises a test control module and a test analysis module. The test control module is operable to generate and transmit first prober and handler (PH) requests to a supervisor module. The supervisor module is operable to transmit first PH commands to a prober and handler for execution thereof. The test analysis module is operable to generate and transmit second PH requests to the supervisor module. The supervisor module is further operable to transmit second PH commands to the prober and handler for execution thereof. The execution of the second PH commands are performed transparently to the test control module.
Abstract:
A number of fault injection circuits and corresponding methods for injecting correlated, uncorrelated, non-persistent and persisting faults at the primary outputs of boundary scan cells are disclosed. Fault data is loaded in the boundary scan cell update latch of all boundary scan cells at which a fault is to be injected. The fault injection circuits generate a fault inject signal which is applied to the control input of the standard cell output selector, an active signal causing the content of the update latch to be applied to the cell primary output. In order to provide for scan testing of the fault injection circuitry, the boundary scan cell shift and update latches and the fault flag latch (if employed) are provided with hold capability so that the contents of these elements can be controlled and their input captured in accordance with standard scan testing techniques.
Abstract:
An improvement in a method of testing a digital circuit or system, having a plurality of scannable memory elements, in accordance with conventional BIST methods in which, at a reference clock, a test stimulus is shifted into the memory elements, the response of the elements is captured and the captured data is shifted out of the elements and analyzed, the improvement comprising controlling the average power consumption of the circuit during the test by suppressing clock pulses from the reference clock during phases of the test that do not require the maximum level of activity or in which the performance of the circuit is not to be evaluated; and, suppressing no clock pulses from the reference clock in phases of the test in which the performance of the circuit is to be evaluated, so that the conditions are substantially as those of normal mode of operation of the circuit.
Abstract:
A method wherein air is separated in an air separation unit (9), the oxygen thus generated is consumed during at least one step (2, 12, 13) of the steel-making process, the resulting gas is at least partially decarbonated, and the at least partially decarbonated gas is used (at 13) in a reduction reaction of the steel-making process. The partial decarbonation step cyclically includes a CO.sub.2 fixation step using a fixation agent, and a regeneration step in which the agent is regenerated in a reactor. Nitrogen generated by the air separation unit (9) is fed into the reactor during the fixation agent regeneration step. The method is useful in combined coal gassification/direct iron ore reduction processes.
Abstract:
A process and installation for the cryogenic purification of impure hydrogen, of the type in which impure hydrogen is cooled under a low pressure PO to a temperature sufficiently low to condense a predetermined proportion of the impurities, by heat exchange in a thermal heat exchange line (3) with purified hydrogen and with a residual fraction containing the expanded preliminarily condensed impurities (in 11, 12) to a low pressure P1. The remaining cold is supplied by the expansion of purified hydrogen in a turbine (8) with gas bearings and the expanded hydrogen is added to the light impurities expanded at the cold end of the heat exchange line. The turbine (8) is supplied with the gas leaving its bearings (17), after cooling of hydrogen at the labyrinthine seal (18) of the turbine is withdrawn under a pressure slightly less than the interstitial pressure Pi which prevails between the rotor (14) and the stator (16) of this turbine.
Abstract:
This invention relates to the reheating of a cold cryogenic fluid by heat exchange with a warm liquid, commonly water. The cold cryogenic fluid first flows into a descending tube and then into a rising tube whereas the water trickles along the tubes and from an upper supply, as far as a base manifold. The invention is particularly applicable to the reheating and revaporization of liquified natural gas.
Abstract:
The invention relates to a variable displacement hydraulic machine, in particular for a motor vehicle, said hydraulic machine comprising a rotating cylinder (10) including a series of axial pistons (12) connected to a first plate (14) axially located on one side of said cylinder within a substantially transverse plane, the slope of which can be controlled, so as to form a first controllable displacement for said machine, wherein said machine is characterized in that the cylinder (10) further comprises a second series of axial pistons (22) connected to a second plate (24), the slope of which is also controllable, said plate being axially located, relative to the first plate (14), on the other side of said cylinder so as to form a second controllable displacement for said machine.
Abstract:
A cutting head with chip collection for cutting a tubular object. The cutting head comprises a frame and gripping, cutting, advancing and sealing units. The gripping unit is used to grip the object and secure its position with respect to the frame. The cutting unit has a motor driving a blade for cutting the tubular object. The advancing unit is used to guide the cutting unit in order to vary a cutting depth of the blade through a cutting area defined by an opening of the frame. The sealing unit has members extending around the cutting area and forming a chamber to contain the chips produced by the blade during a cutting. A suction conduit communicating with the chamber allows drawing the chips and conveying them toward a chip collecting outlet.
Abstract:
A system for transmitting data, including at least one data transmission network (10), one or several client machines (12, 14, 16) connected to the network and one or several server machines (18, 20, 22) which are also connected to the network and which can be connected at a given moment to one of the server machines in order to exchange data therewith. The system includes at least one central server (24) which is connected to the network. Each of the server machines have several connection devices enabling a permanent connection to be established with the central server, and each of the client machines have client connection devices enabling a provisional connection to be established with the central server.