Disclosed is a semiconductor memory (18, 20, 100, 200) having a hierarchical bit line architecture including local bit lines (LBL.sub.1, LBL.sub.2) on a lower fabrication layer, coupled to memory cells (MC), and master bit lines (MBL) on a higher fabrication layer, each coupled to an associated sense amplifier (SA.sub.i). Local bit lines disposed in any given column are coupled to different numbers of memory cells, i.e., the local bit lines have different lengths (L1, L2) over the memory cells. A hybrid configuration is preferably employed in which one local bit line (LBL.sub.1) in a column is directly coupled via a switch (25.sub.1) to an associated sense amplifier, whereas the other local bit lines in the column (LBL.sub.2 -LBL.sub.4) are operatively coupled to the sense amplifier via the master bit line. The different local bit line lengths are preferably selected such that total bit line capacitance with respect to any of the memory cells is substantially equalized, thereby improving data retention time for the memory.

The hierarchical or "segmented" bit line architecture was developed in recent years in order to increase the integration density of memory chips. This architecture allows for a reduced number of space-consuming sense amplifiers for a given number of memory cells, thus reducing chip size or increasing memory capacity for a given size chip.
In a conventional hierarchical bit line architecture, each column of the memory cell array includes a number of equal length local bit lines (LBLs), directly connected to the memory cells, and a master bit line (MBL) composed of a high conductivity metal disposed at a higher fabrication layer than the local bit lines. For example, each local bit line may connect to several hundred memory cells. Each master bit line is connected directly to a sense amplifier and is selectively coupled to a number of local bit lines in a common column via a number of switches. To access (read, write or refresh) a memory cell connected to a particular local bit line, the switch connecting that local bit line to the master bit line is closed while the other switches in the column are opened.
FIG. 1 illustrates a memory bank 10 of a prior art semiconductor memory utilizing a hierarchical bit line architecture. The memory bank is divided into subarrays of memory cells, e.g., MAa to MAd, and a number of sense amplifier banks such as 12.sub.j, 12.sub.j+1, 12.sub.j+2. In the shown configuration, the sense amplifiers SA.sub.i within each sense amplifier bank are arranged in a shared configuration, such that each sense amplifier amplifies signals from memory cells on both sides thereof in a time multiplexed manner. Each subarray has N columns C.sub.1 -C.sub.N ; however, since the sense amplifiers are shared, each SA bank has N/2 sense amplifiers. Each sense amplifier, e.g., SA.sub.2 of bank 12.sub.j+1 is connected on each side to a master bit line pair consisting of a true master bit line MBL and a complementary master bit line MBL. In this example, each true master bit line MBL is connected to four true local bit lines LBL.sub.1 to LBL.sub.4 of equal length L, and each complementary master bit line MBL is connected to four complementary local bit lines LBL.sub.1 to LBL.sub.4 . The sense amplifier amplifies a differential voltage between the pair of master bit lines--one master bit line is used to carry a reference voltage while the other carries a cell signal transferred thereto by activation of a selected memory cell MC. A word line WL.sub.j in the jth row is activated in accordance with the row address to access the selected memory cell. The configuration shown is known as a folded bit line architecture, wherein the true and complementary bit lines run side by side one another in close proximity. If an open bit line configuration were used, the complementary master bit line would reside on the opposite side of the sense amplifier as the true master bit line.
FET switches S are each coupled between an end portion of a respective local bit line and a connection point P connecting the corresponding master bit line. Memory cells coupled to a particular local bit line are accessed by closing the corresponding switch S and opening the other switches in the corresponding column by appropriate control voltages on control lines 23.sub.1 -23.sub.4.
In general, bit line capacitance is proportional to bit line length. As such, bit line length is limited by the maximum bit line capacitance that can be tolerated. The maximum capacitance is generally determined by the allowable sensing margin and the power dissipation. With the hierarchical bit line architecture, the master bit line capacitance per unit length is less than the local bit line capacitance per unit length, since the local bit lines are directly coupled to the memory cells which significantly contribute to the local bit line capacitance, whereas the master bit lines are not directly coupled to the cells. Thus, for a given column length, the total capacitance can be significantly less than in a non-hierarchical layout (i.e., layouts with only one layer of bit lines, each extending the entire column length and directly coupled to the memory cells). Therefore, by using a hierarchical architecture, less space-consuming sense amplifiers are needed for a chip with a specific number of memory cells. That is, the architecture permits each sense amplifier to be used for more cells, coupled to the local bit lines and one long master bit line, thereby reducing the number of sense amplifiers per chip. A smaller chip size is thus possible, provided that the area allocated to the switches S and additional control circuitry does not exceed the area saved by reducing the number of sense amplifiers.
FIG. 2 illustrates a variation of the above-discussed hierarchical bit line architecture. The shown configuration will be referred to hereafter as a "hybrid" type hierarchical architecture. FIG. 2 shows the case in which only two local bit line pairs (LBL.sub.1, LBL.sub.1 ) and (LBL.sub.2, LBL.sub.2 ) are disposed on each side of an associated sense amplifier SA.sub.i. In each column C.sub.i of a memory cell subarray, the local bit lines nearest the sense amplifier, i.e., LBL.sub.1 and LBL.sub.1 , are connected to the drain or source of a respective switch 25.sub.1, with the other side of the switch connecting directly to the sense amplifier electronics at a circuit node 63. This circuit node 63 is generally the same circuit node that connects the sense amplifier electronics to the corresponding master bit line MBL or MBL. A switch 25.sub.2 is coupled between each far side local bit line LBL.sub.2 and LBL.sub.2 and the corresponding master bit line at a connection node d. Gaps g separate LBL.sub.1 from LBL.sub.2 and LBL.sub.1 from LBL.sub.2 . To access a memory cell MC coupled to LBL.sub.1 or LBL.sub.1 , switches 25.sub.1 are turned on (closed) while switches 25.sub.2 are off, and vice versa to access cells coupled to the far side local bit lines LBL.sub.2 and LBL.sub.2 . Thus, memory cells coupled to the far side local bit lines are operatively coupled to the sense amplifier via the far side local bit line and the master bit line, whereas those cells coupled to the near side local bit line are coupled to the sense amplifier only via the near side local bit line. As such, the configuration of FIG. 2 is referred to as a hybrid. If more than two local bit line pairs are used on each side of the sense amplifier, then the path connecting the memory cells coupled to the near-side local bit lines LBL.sub.1 and LBL.sub.1 consists of only the local bit line whereas the paths connecting the sense amplifier to the other memory cells in the column consists of the master bit line in series with the respective local bit line.

Semiconductor memory having hierarchical bit line architecture with non-uniform local bit lines


A data transport service of a provider network provide isolated and flexible network data transmission between different computing infrastructure collections of the provider network (e.g., between different geographical regions) for different users. The data transport service may receive a request from a user for assignment of a channel. The request specifies a desired capacity of the channel to transmit data from a computing infrastructure collection to another a computing infrastructure collection. Based on the requested capacity for the channel, the data transport service may reserve, for the channel, network resource capacity to transmit the data between the infrastructures and reserve, for the channel, compute instance capacity to ingest the data and to send the data between the infrastructures using the reserved network resource capacity. The reserved network resource capacity and reserved compute instance capacity are dedicated to the channel and are unavailable for use by other channels.

Service providers may offer various online services to clients around the globe by using an extensive provider network. Therefore, provider networks may include many different data centers located in different regions around the world to provide services efficiently at a local level. For various reasons, a service located at a data center in one region may need to transfer a large amount of data to a data center in another region. For example, a client may copy data from one region to one or more other regions to maintain backups of the data.
Some clients may require hard bounds on replication delay between regions (e.g., the time between writing data to a source in one region and copying the data to a destination in another region). For example, a particular client may require the replication delay to be an hour or less for regulatory compliance or to maintain business continuity in case of a failure at the source region. The available bandwidth for transmitting data within a given region typically far outstrips the available bandwidth for transmitting data between regions. Moreover, many different clients may be competing for cross-region bandwidth at any given time. Therefore, it may be difficult to meet the replication delay requirements for multiple clients at once. Consequently, some clients may not meet their replication and backup requirements.
While embodiments are described herein by way of example for several embodiments and illustrative drawings, those skilled in the art will recognize that embodiments are not limited to the embodiments or drawings described. It should be understood, that the drawings and detailed description thereto are not intended to limit embodiments to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope as defined by the appended claims. The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims. As used throughout this application, the word "may" is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words "include," "including," and "includes" mean including, but not limited to.

Isolated and flexible network data transmission between computing infrastructure collections


A hydraulic parking brake controller for a motor vehicle for controlling the operation of a parking brake of the transmission output-shaft mounted type in response to the operating unit. The controller comprises a primary control and a secondary control. The primary control actuates and releases the parking brake at a first rate. The secondary control actuates the parking brake at a second rate slower than the first rate in an instance in which the parking brake is in the released state and the operation unit malfunctions. If a circuit break should occur in the operation unit while the parking brake is in the released state, the secondary control actuates the parking brake at the second rate. The parking brake is thus not actuated suddenly in the event of an abrupt wire disconnection, such that the braking action is dampened.

The present invention relates generally to a hydraulic parking brake controller of a motor vehicle and, more specifically, to a hydraulic parking brake controller used in construction machines and industrial vehicles in order to control, in response to an operation unit, the operation of a hydraulic parking brake provided at the vehicle output shaft.
Parking brake controllers have been installed in construction machines and industrial vehicles. In those vehicles a drum type or a disc type parking brake is provided on the output shaft of a vehicle transmission, which brake is operated by an operator manually in order to brake the output shaft.
Nowadays, other brake controllers have been developed in which a normally-engaged type parking brake on the transmission output shaft is released by hydraulic pressure. A conventional brake controller of this type is shown in FIG. 5 and illustrates a parking brake 2 provided around an output shaft 1 of a transmission. The parking brake 2 comprises a case 2a secured to a housing of the motor vehicle, a plurality of brake discs 3, a piston 4 and a spring 5 for urging the piston 4 axially against brake discs 3. Some of the brake discs 3 are engaged with the case 2a so as to be slidable in the axial direction yet non-rotatable. Other of the brake discs 3, interlaminated with the former discs, are non-rotatably engaged with the output shaft 1 and are slidable in the axial direction. The piston 4 is driven leftward in FIG. 5 by the spring 5 to compress the brake discs 3, thereby braking the output shaft 1.
A directional control valve 7 is connected to an oil chamber 6 defined by the case 2a of the parking brake 2. The directional control valve 7 comprises a case 7a, a piston valve 8 and a solenoid 9 which extends or retracts the piston valve 8 in order to control the engagement and the release of the parking brake 2. The directional control valve 7 is connected to a hydraulic power source 10 and a reservoir 14. The hydraulic power source supplies hydraulic fluid to the directional control valve 7. The solenoid 9 provides on-off control in response to signals from an operation unit 11 installed at the driver's seat, which unit 11 is connected to an electric source 13 through a main switch 12.
When the contact of the operation unit 11 is switched over to its actuation terminal, the solenoid 9 switches off, moving the piston valve 8 to the position shown by the solid lines in FIG. 5. As a result, the hydraulic fluid in the oil chamber 6 of the parking brake 2 drains into the reservoir 14 through the oil chamber 7a of the directional control valve 7 whereupon the brake discs 3 are compressed under the urging force of the spring 5 between the brake housing and the piston 4. Thus the output shaft 1 is braked.
When the contact of the operation unit 11 is switched over to its release terminal, the solenoid 9 switches on, moving the piston valve 8 to the position shown by the dashed lines in FIG. 5. Thereupon, hydraulic fluid is supplied to the oil chamber 6 of the parking brake 2 from the hydraulic power source 10, so that the piston 4 moves rightward in FIG. 5 against the urging force of the spring 5, whereby the output shaft 1 can rotate freely.
If the circuit to the solenoid 9 in the aforedescribed parking brake controller, should become broken or short, the solenoid 9 switches off, actuating the parking brake 2. Thus in the event of electrical malfunction or it the hydraulic system is otherwise out of order, the parking brake will nonetheless be engaged.
However, in the conventional brake controllers, the hydraulic fluid in the oil chamber 6 of the parking brake 2 is drained very suddenly when the solenoid 9 is deactivated on account of electrical malfunction such as wire breaks, such that the brake is engaged too suddenly. The strong jolting of such sudden braking can be very dangerous to machine operators.

Parking brake controller with slower actuation in the event of a malfunction


A system for mapping electrical conductivity of the seafloor incorporates a plurality of data logging units, where each unit (100) is an assembly adapted for deployment at a location on the seafloor for measurement of horizontal electric and magnetic fields. Rigidly attached and extending vertically from the unit assembly is a vertically-oriented substantially rigid arm (158) having a pair of vertically-displaced electrodes (160, 162) disposed on the arm to create a vertically-oriented dipole antenna. The electrodes are in electrical communication with an amplifier located within the assembly which generates an amplified signal which is then provided to a data logging processor also located within the assembly. The processor collects time series of amplified electric field and magnetic signals over a predetermined period of time.

The magnetotelluric (MT) method is an established technique which uses measurements of naturally occurring electromagnetic fields to determine the electrical resistivity, or conductivity, of subsurface rocks. An MT survey employs time series measurements of orthogonal components of the electric and magnetic fields, which define a surface impedance. This impedance, observed over a broad band of frequencies and over the surface, determines the electrical conductivity distribution beneath that surface, with horizontal layers of the earth being mathematically analogous to segments of a transmission line. Principal factors affecting the resistivity of subsurface materials include temperature, pressure, saturation with fluids, structure, texture, composition and electrochemical parameters. Resistivity information may be used to map major stratigraphic units, determine relative porosity or support a geological interpretation. A significant application of MT surveying is oil exploration. An MT survey may be performed in addition to seismic, gravity and magnetic data surveys. A combination of data from two or more different survey methods leads to a more complete understanding of subsurface structure than may be possible through the use of any single technique alone, particularly where the structure is such that measurement using a given technique may be contraindicated. For example, certain structures such as sediments buried under salt, basalt or carbonate have poor seismic performance and productivity. These structures generate strong reflections and reverberations, making imaging of the buried sediments difficult using acoustic methods alone. On the other hand, because the MT method does not involve the measurement of responses to artificially-created seismic events, it can be utilized in lieu of or in combination with seismic methods to minimize the error induced by reflections.
While the MT method has been used on land as an aid to petroleum exploration for many years, its application to marine continental shelf exploration is more recent. Remote reference data acquisition, robust data processing and multidimensional modeling and inversion have been required to produce meaningful responses to signals available from MT surveys.
Significant progress has been made in recent years in the ability to collect seafloor MT data. In the past, one primary reason for the limited use of MT for seafloor mapping was that high frequencies are rapidly attenuated by seawater, leading to a dramatic loss of electric and magnetic field power on the seafloor at periods shorter than 1000 seconds. However, to be useful for mapping continental shelf structures at depths relevant to petroleum exploration, MT measurements should be made at periods between 0.1 and 1000 seconds. The present inventor has addressed these difficulties by developing a system and method disclosed in U.S. Pat. No. 5,770,945, issued on Jun. 23, 1998, and entitled "Seafloor Magnetotelluric System and Method for Oil Exploration", which is commonly assigned with the present application and incorporated by reference herein. The system and method disclosed in that patent utilize horizontal electric and magnetic field measurements to map seafloor geological structures of interest in oil prospecting. An important improvement provided by the disclosed system and method is derived from the use of higher frequencies, on the order of 1 Hz, making it more appropriate for petroleum exploration compared with the systems in the prior art.
Measurement of horizontal fields alone provides only part of the information that is desirable for detailed mapping of geologic structures. While vertical electric fields do not exist at the surface on land, they are present in the ocean. Therefore, in order to fully exploit the MT technology for seafloor exploration, it would be advantageous to provide for measurement of vertical magnetotelluric impedances, which are preferentially sensitive to lateral variations in geological structure. Previous attempts to measure vertical e-fields have used noisy, tethered instruments, e.g., electrodes attached at intervals along a length of flexible cable which is dragged behind a vessel. For example, see U.S. Pat. No. 4,047,098 of Srnka or U.S. Pat. No. 2,839,721 of DeWitte. These prior art systems also used low frequency amplifiers such that they were subject to the above-described frequency limitations for application to seafloor oil exploration.
An additional use of the instrument described in U.S. Pat. No. 5,770,945 is for controlled source electromagnetic surveying, in which an electromagnetic (EM) transmitter is placed or towed in seawater, preferably at or near the seafloor. The amplitude and phase of the transmitted signals are then used to determine the electrical resistivity of subsurface rocks and fluids. Controlled EM source methods are well known in the art and have become almost routine for mapping of electrical conductivity of the seafloor in very shallow to deep ocean water, achieving seafloor penetration depths as great as 30 km in 5 km of water. However, these known methods have failed to recognize and/or take advantage of the vertical electric field and its ability to measure lateral variations in seafloor subsurface structure.
Accordingly, the need remains for a system and method which can exploit a vertical field's ability to measure lateral variations in the geological structure of the seafloor.

Method and system for seafloor geological survey using vertical electric field measurement

The Regents of the University of California


The present invention relates to novel, stable recombinant gamma interferons exhibiting in greater or less degree the antiviral and antiproliferative activity in humans and pH 2 labile properties characteristic of native human gamma interferon. The amino acid sequence of such an interferon comprises, from the N-terminus:

The present invention relates to the field of recombinant DNA technology, to means and methods utilizing such technology in the preparation of recombinant gamma interferons having enhanced stability, to their production and to the various products of such production and their uses.
The publications and other materials used herein to illuminate the background of the invention and in particular cases to provide additional details respecting its practice are incorporated herein by reference and for convenience are numerically referenced in the following text and respectively grouped in the appended bibliography.
Human interferons can be classified in three groups on the basis of different antigenicity and biological and biochemical properties. The first group comprises a family of leukocyte interferons which are normally produced mainly by constituent cells of human blood upon viral induction. These have been microbially produced and found to be biologically active (1, 2, 3). Their biological properties have prompted their use in the clinic as therapeutic agents for the treatment of viral infections and malignant conditions (4).
In the second group is human fibroblast interferon, normally produced by fibroblasts upon viral induction, which has likewise been microbially produced and found to exhibit a wide range of biological activities (5). Clinical trials also indicate its potential therapeutical value. The leukocyte and fibroblast interferons exhibit very clear similarities in their biological properties despite the fact that the degree of homology at the amino acid level is relatively low. Both groups of interferons contain from about 165 to about 166 amino acids and are acid stable proteins.
Human gamma interferon (also variously-referred to as immune interferon, xcex3-interferon, IIF or IFN-xcex3) exhibits the antiviral and anti-proliferative properties characteristic of the interferons but, in contrast to leukocyte and fibroblast interferons, is pH 2 labile. Prior to the production of gamma interferons via recombinant DNA technology, It had been produced mainly upon mitogenic induction of lymphocytes. Human gamma interferon is clearly antigenically distinct from the leukocyte and fibroblast interferons. Gray, Goeddel and co-workers were the first to report expression of a recombinant gamma interferon (6), which has proven to exhibit the characteristic properties of human gamma interferon, i.e., anti-viral and anti-proliferative activity coupled with pH 2 lability. The recombinant gamma interferon of Gray and Goeddel, as produced in E. coli, consisted of 146 amino acids, the N-terminal portion of the molecule commencing with the sequence CYS-TYR-CYSxe2x80x94. Derynck and others subsequently reported (7) a further recombinant gamma interferon having the same N-terminus and a single amino acid substitution, the polypeptide perhaps constituting an allelic variant of that earlier reported in reference (6). Other workers have reported the production of still further recombinant gamma interferons in which one or more of the amino acids present in Goeddel and Gray""s original publication (6) have allegedly been substituted.
For example, Alton et al. (17) report on a series of IFN-gammas wherein a single amino acid substitution at position 81 of the Gray et al. (6) gamma interferon resulted in an IFN-gamma that retained only 70 percent of the activity (on a relative basis) and wherein an additional deletion of the cys-tyr-cys at positions 1, 2, 3 of this IFN-gamma further reduced relative activity resulting in an IFN-gamma having only 49 percent of the Gray et al. (6) gamma interferon.
In our hands, recombinant gamma interferons whose N-terminal amino acid sequence comprises cysteine residues have proven problematic from the standpoint of oligomerization which may involve participation of sulfhydryl groups of one or more of the cysteine residues in disulfide bond formation. Our inability to completely reduce these putative disulfide linkages suggests the problem may be more complex, possibly also involving reaction through the hydroxyl function of the cysteine-bounded tyrosine residue. These recombinant interferons have proven somewhat unstable and, whether resulting from such instability or otherwise, have proven of less than optimal utility.
The present invention relates to recombinant gamma interferons having enhanced stability and activity. In the most preferred embodiment we provide a recombinant gamma interferon comprising the amino acid sequence (hereinafter xe2x80x9cfull sequencexe2x80x9d), extending from the N-terminus:
wherein X is a methionine residue or hydrogen and Y is a glutamine residue or, where X is a hydrogen, either a glutamine or pyroglutamate residue, as well as various analogs thereof in which specified portions of the carboxy terminal of the foregoing sequence are absent. The invention also provides corresponding cloned genes, expression vectors comprising them, and transformants useful in the production through recombinant DNA technology of the interferons of the invention. The preferred recombinant gamma interferons of the invention (as compared to those previously characterized in the literature) appear to most closely approximate the true amino acid sequence of native gamma interferon, the latter of which we have now purified from native sources and fully characterized. Preferred embodiments of the invention exhibit greatly improved stability and activity relative to those previously described in the literature.

Recombiniant gamma interferons having enhanced stability and methods therefor

Abstract: wherein X is a methionine residue or hydrogen and Y is a glutamine residue, or, where X is hydrogen, Y is either a glutamine or a pyroglutamate residue.


A rotary absorption heat pump assembly. The assembly comprises a generator (2), condenser (3), evaporator (4), absorbent cooler (5), and absorber (1), all operatively associated to function as components of an absorption-type heat pump of high efficiency and superior operating characteristics. The heat pump is characterized by the presence of a tapered cylindrical absorber (1) which receives and processes, in the form of a very thin peripheral film ("d"), a predetermined amount of absorbent solution. The absorber (1) is arranged in abutting end-to-end relationship to the generator (2), with which it communicates. The condenser (3) and evaporator (4) are arranged end-to-end outside of the absorber (1) and absorbent cooler (5), concentrically therewith and radially spaced therefrom.

Absorption machines used as chillers and ice makers predate similar duty vapor compression machines by the better part of a century. With the advent of universal electrical usage and, more so, with the introduction of the chlorofluorocarbon refrigerants, vapor compression machines supplanted but did not completely eliminate absorption machines from the marketplace. Since the 1950's, vapor compression machines manufactured to condition room air not only cool in the Summer but heat in the Winter thereby assuming the characteristics of true heat pumps. Heat pumps thus are of two categories: rotary absorption heat pumps (RAHP's) and vapor compression heat pumps (VCHP's).
The conditions which initially heavily favored VCHP's in the marketplace have subsequently been somewhat altered. The world has become more conscientious about conserving energy, especially since the large increase in the price of energy which occurred during the mid 1970's. The economic balance here favors the absorption process, because it can utilize low-grade waste heat efficiently.
Also, with the recent recognition of the destructive behavior of chlorofluorocarbons (CFC's) on the earth's protective ozone layer, the heretofore ideal class of refrigerants for use in VCHP's has been eliminated, thus further tilting the balance in favor of the absorption process.
The RAHP's differ from conventional VCHP's both in their operating cycle and in their construction. The common cycle components in RAHP's and VCHP's are the evaporator and the condenser but thereafter the similarity ends. In the VCHP's, the vapor produced in the evaporator is increased in pressure by means of a mechanical pump and at the higher pressure it is cooled and liquified in the condenser. Subsequently, it is returned to the evaporator in order to complete the cycle. In the RAHP's, the refrigerant vapor produced in the evaporator is absorbed in a deliquescent material located within a component termed the absorber. The diluted deliquescent material is then transferred to a component named a generator within which the refrigerant vapor is separated from the material and its pressure is increased by the application of heat. The vapor at higher pressure is subsequently directed to a condenser wherein it is cooled and liquified before it is returned to the evaporator in order to complete the cycle.
Essentially, the absorber, generator, and deliquescent material or absorbent of RAHP's replace the mechanical compressor of VCHP's. In place of the mechanical energy needed to drive the compressor of VCHP's the RAHP's employ low-grade heat to separate the refrigerant from the absorbent material and, concomitantly, increase the refrigerant vapor pressure in the generator.
In order to capitalize on the advantages accruing to rotation, rotary VCHP's have been built and tested. They have proven to be more compact and quieter in operation than stationary VCHP's. However, rotating seals have compromised hermeticism and market acceptance has not been achieved.
In order to retain object hermeticism and to simultaneously employ waste heat, the rotating VCHP construction disclosed in Doerner U.S. Pat. No. 3,863,454 has been advocated. However, the Doerner design retains its dependence on clorofluorocarbons for the refrigerant and possibly for the boiler power fluid, in addition to requiring a high-temperature heat source for its operation.
It is the general purpose of the present invention to formulate the absorption heat pump process into a rotating unitary construction wherein the properties of rotation are used to simplify the procedure so as to result in the provision of a compact and mechanically simple heat pump unit, thereby enhancing the popularity of the absorption type unit in the marketplace.
It is another important object of the present invention to conserve energy by circumventing the wasteful process of converting the energy in primary fuel to mechanical or electrical energy, which energy subsequently is targeted to operate cooling equipment.
Still a further object of the present invention is the provision of a rotary absorption heat pump unit which is of compact, unitary construction; which is tolerant of changes in air temperature, operating rotational speed and generator temperatures; and which minimizes the undesired occurrence of crystallization of the absorbent solution during operation or down time of the heat pump unit.
Another object of the present invention is to reduce the physical size of RAHP's by constructing their evaporator and condenser components to be concentric and coaxial with the absorber and generally locating them radially outboard from the absorber.
It is a further object of the present invention to improve the efficiency and capacity of RAHP's by formulating a very thin film of absorbent within the absorber of such a thickness and of such a residence time that the absorption process is brought to an optimum completion.

Rotary absorption heat pump of improved performance


With a simple configuration, responsiveness between an electronic control unit and a load drive circuit is monitored without deteriorating characteristics of the load drive circuit. The load drive circuit according to the present invention diagnoses an abnormality in responsiveness of a switch element that drives a load based on a drive command of the switch element and a signal at an output terminal of the switch element.

In a fuel injection control device for an internal combustion engine, a drive device (load drive circuit) includes a switch for controlling energization of a fuel injection valve, and controls the switch according to a fuel injection command which is computed by the microcomputer, thereby controlling the energization of the fuel injection valve. The fuel injection valve is opened due to the energization of the fuel injection valve to inject fuel.
In recent years, as a countermeasure for improving an exhausting performance of the internal combustion engine, a multi-stage injection control in which the fuel is injected at least a plurality of times in one combustion cycle has been applied. In the multi-stage injection control, the fuel injection valve is opened plural times during one combustion cycle. In this case, accuracy of injection timing or injection amount has been required as compared with the conventional fuel injection. Therefore, the fuel injection control device is required to monitor whether or not the drive device correctly responds to each fuel injection command.
The following PTL 1 discloses a fuel injection control device in which an electronic control unit that calculates a fuel injection amount and a drive device that drives a fuel injection valve are provided separately. In PTL 1, the electronic control unit energizes the fuel injection valve in response to a fuel control signal based on a fuel injection command which is computed by the electronic control unit. The fuel injection control device detects a drive current for the drive device to energize the fuel injection valve, and outputs the detection signal to the electronic control unit. The electronic control unit compares the fuel injection command or the injection control signal based on the fuel injection command with the detection signal, and determines, based on the comparison result, whether or not a drive circuit correctly outputs a drive signal to the fuel injection valve corresponding to the fuel injection command.

Load drive circuit and load drive system


The invention is concerned with an integrated process for the manufacture of polymer and/or composite products, comprising the integration of processing operations to achieve a plurality of material conversion steps, such as impregnation, consolidation and bonding, within one single controlled fabrication cycle. The process includes an in-situ final preparation of at least one composite preform at the location of the moulding operation and an integrated moulding operation comprising a step of providing an additional matrix-functioning material into the mould to at least partially enclose the composite preform, the operation of providing the additional matrix-functioning material providing the pressure for an in-situ final consolidation of the composite product.

The present invention relates to a process for the manufacture of polymer and/or composite products and to the related equipments.
Polymers and polymer composites have the advantages of weight saving, high specific mechanical properties and good corrosion resistance which make them indispensable materials. Nevertheless, manufacturing costs are sometimes detrimental, since they can represent a considerable part of the total costs. Furthermore, the production of complex shaped parts is still a challenge for the composite industry. Parts with relatively simple geometries are common place today for composites; pre-peg manufacturing, autoclave, filament winding, pultrusion, etc. are examples of well-developed technologies. But the production of complex 3-dimensional parts usually requires injection moulding or compression moulding of short fibre composites (xe2x80x9cengineering compositesxe2x80x9d). The drawback of short fibre reinforced composites is their considerable lower intrinsic specific mechanical properties. Assembly technologies used to obtain complex geometry for advanced composites are sometimes inefficient and not cost-effective.
The proper selection of a material system and process for manufacture of composite parts depends on a number of factors including material processability, design, part performance, and manufacturing economics [see in particular J.-A. E. M{dot over (a)}nson, New demands on manufacturing of composite materials, in High-performance composites, Ed. K. K. Chawla, P. K. Liaw, S. G. Fishman, TMS, Warrendale, Pa., (1994)].
As shown in FIG. 1, which shows a mapping of composite processing techniques with respect to their ability for complex shaping and annual production volumes, the number of parts to be produced and the required part size and complexity influence the selection of a suitable manufacturing process [see in particular W. J. Lee and J.-A. E. M{dot over (a)}nson, xe2x80x9cFactors Influencing Process Selection and Processingxe2x80x9d (Proceedings: Polymer Composite Applications for Motor Vehicles, SAE International, Detroit, USA, Feb. 25, 1991) 35.]. For low number of parts to be manufactured, a process which requires lower investment in tooling and equipment costs but longer cycle times and more labour may be favoured.
The limited potential for complex shape forming offered by advanced composite materials leaves little scope for design freedom in order to improve mechanical performance and/or integrate supplementary functions. This has been one of the primary limitation for a wider use of advanced composites in cost-sensitive large volume applications. Contrary to most traditional composite applications, many applications in, for example, the mechanical industry are small and are of more complex three-dimensional shapes, which are normally produced by casting techniques.
Traditional injection moulding, provides almost unlimited possibilities for shaping. Here, considerably greater design freedom for mechanical performance is achieved with a considerably cheaper material. However, the intrinsic mechanical properties are also lower, given the short fibre materials used, and so the potential for both load bearing and weight saving is diminished.
In most cases performance improvement has been achieved by the development of material systems with improved intrinsic properties (fibre types, resin systems and fibre content). These developments have also driven up raw material costs and the interest in branches with cost-sensitive applications has been reduced, slowing down the introduction of composite applications.
Increased design freedom nevertheless opens many possibilities for engineering solutions which may considerably increase the interest for composite materials in structural applications. FIG. 2 gives an indication of this dilemma. Most of the manufacturing techniques used today for composite materials may be placed on the exponentially-shaped band as indicated in the diagram.
Given the demands of many industries today, it is obvious that. the desired direction for future development is towards the upper right-hand corner of the diagram. The development of material systems with both high intrinsic properties and improved formability for complex shapes may only be ensured by close interaction during the development of the material preforms and of the processing techniques.
In this view, several material systems and manufacturing techniques are today under development, aiming to improved complex shape forming of advanced composites under attractive manufacturing conditions. Novel material systems using either pre-impregnated preforms or post-shaping impregnation are being closely studied by several research groups [see in particular A. G. Gibson and J.-A. E. M{dot over (a)}nson, xe2x80x9cImpregnation Technology for Thermoplastic Matrix Composites,xe2x80x9d Journal of Composites Manufacturing, 3 (4) (1992), 223-233, F. Neil Cogswell, Thermoplastic Aromatic Polymer Composites (Oxford: Butterworth-Heinemann, 1992) and J.-A. E. M{dot over (a)}nson, xe2x80x9cProcessing of Thermoplastic-based Advanced Compositesxe2x80x9d, Advanced Thermoplastics and their Composites, ed. H-H. Kausch (Munich: Carl Hanser Verlag Gmbh. 1992), 273]. Powder preform techniques have so far been the most explored route to improved complex formability with thermoplastic-based composites, but automated tape placement methodologies have also shown promise [see in particular K. V. Steiner, E. Faude, R. C. Don and J. W. Gillespie Jr., xe2x80x9cCut and Refeed Mechanics for Thermoplastic Tape Placement,xe2x80x9d (Proceedings of the 39th International SAMPE Symposium, Anaheim, Calif., 1994), 2627].
The potential conversion routes for composites, from fibre and matrix to finished products are illustrated on FIG. 4. Traditionally each processing steps (FIG. 3) are developed by separate companies and semi-products delivered to the next link of the processing chain.
It is by no means clear that an optimal matrix material for a composite, in terms of fibre-matrix adhesion, is suited for the other demands set upon a composite part. For instance, environmental resistance and tribological performance may not always be given by a typical matrix material. Furthermore, a high fibre content will normally have a negative influence on the surface finish of the product. The free-forming potential of neat polymers or short fibre systems will always be superior to that of continuous fibre materials. In addition, a well-known strategy to reduce cost is to reduce the number of sub-components in complex structures while integrating multiple functionality. To meet several of these requirements with one material or one processing technique may not be possible.
Considering these points it is clear that higher flexibility of the composite materials is required in many applications to increase the material""s attractiveness to design engineers. A more integrated approach using complementary materials and processes in the fabrication of the part would be desirable.
The logical step seemed therefore to integrate as far as possible the individual processing operations illustrated on FIG. 4.
The aim of the present invention is to propose novel processing techniques and equipments permitting to remedy to the disadvantages of the existing techniques and in particular to reduce manufacturing costs by the suppression of intermediate processing and assembly stages.
Therefore, the invention concerns a novel processing technique where neat polymers, reinforcements and/or preforms and/or composites are combined in a single operation, by combining several processes into a single step or as a sequence of steps in rapid succession, where simultaneous material and process integration is achieved.
As shown in FIG. 7 this integrated processing technique offers larger design freedom, performance integration and multifunctionality in complex shaped composite parts.
An object of the present invention is an integrated processing unit allowing an automated combination of processing steps such as tow placement, consolidation, internal stress release, press-forming, horizontal and vertical injection moulding, inner-gas-forming, slit-die extrusion and liquid injection for integrated multi-component or multi-functional parts.
Another object of the invention is a sheet impregnation unit comprising several stations for manufacturing of composites preforms such as fibre lay-up, powder lay-up, impregnation, preconsolidation and lofting.
Still another object of the invention is a multi-task robotised unit permitting an automatic control synchronisation between all processing units of the equipment, such in particular tow placement, composite preparation, combination of preforms and manipulations of tools, preforms and processed parts.
Still another object of the invention is a tow impregnation unit arranged to deliver tow preformdirectly into the moulds.
Integrated processing is the use of an automated sequence of forming operations in rapid succession. A comparison of processing cycles for conventional and integrated processing to produce a single complex component is illustrated on FIG. 5, which refers to conventional processing, and FIG. 6, which refers to integrated processing, where 1 refers to a first processing step, 2 to a second processing step, 3 to bonding of processed components issued of said first and second steps, T represents a transfer to another equipment and F the finishing operations.
Further opportunities lie in the combination of materials of high mechanical performance with engineering plastics in the same component.
Integrated processing provides the means of using advanced composites for high performance, and engineering plastics for geometry and appearance, in demanding structural components with maintained design benefits and attractive manufacturing costs.
The integrated processing facilitates an automated consecutive processing cycle, including both high and low pressure forming, techniques. Furthermore, the equipment permits pre-impregnated preforms, drapable preforms for post-shaping impregnation and short fibre compounds to be processed. It is obvious that inter-material bonding and management of internal stress generation play an important role in the process. Initial work performed on classical presses has shown that by careful selection of materials and processing conditions sufficient bond strength may be obtained at cycle times in the order of minutes [G. D. Smith, S. Toll and J.-A. M{dot over (a)}son, xe2x80x9cA study on Interface Healing in Polypropylene Processingxe2x80x9d (Flow Processes in Composite Materials ""94) and G. D. Smith, S. Toll and J.-A. E. M{dot over (a)}son, xe2x80x9cIntegrated Processing of Multi-Functional Composite Structures,xe2x80x9d (Proceedings of the 39th International SAMPE Symposium, Anaheim, Calif., 1994), 2385].
The following objectives have been considered:
Integration of Materials
Investigation and modification of compatibility between integrated polymeric materials (neat polymers, preforms and composites)
Optimisation of adhesion mechanisms during integrated processing sequences
Evaluation of bond strength and management of stress state in multi-component parts
Prediction of dimensional stability and durability of integrated parts
Integration of Manufacturing Processes
Integration of fast, low pressure processing techniques
Combination of the process windows of all integrated materials
Integration and automation of process sequences
Improvement of equipment flexibility and cost-efficiency
The performance of a structural part does not depend only on geometric parameters. For composites more than for other traditional materials, material properties and functional requirements are part of any optimum design. According to the invention, the integration of various material types into complex shaped parts introduces new perspectives in parts design.
Up to now, combinations of several polymers have been studied by numerous industries for different applications. For example multimaterial injection has-been used for automotive multicolor lens or food containers. Electronics and hygiene/cosmetics industries are other application sectors. Coextrusion is another example of a technique successfully developed for multilayer packaging.
The integration processing according to the invention is appealing and one can now combine reinforced polymers and composite preforms with surrounding neat polymers. By a judicious disposition of high tailorable intrinsically stiff composites the load transmission is optimised. Then non-structural components are moulded to keep the composite in place and to fulfil additional requirements like surface properties, and/or other supplementary functions.
Different types of materials are envisaged for integration, neat and modified thermoplastic and/or thermoset polymers, reinforcements, particles and fibres reinforced polymers, composites, metals. Subsequently and as illustrated in FIG. 8, various functions can be integrated in one part: complex geometry, load transmission and stiffness 4, connection using inserts and integration of sub-structures 5 (channels, doors, fastening elements . . . ), wear and corrosion resistance, surface finishing 6 and heat insulation or transfer.
Consequently, owing to material integration, multi-functionality and fine tailoring of performances (FIG. 9) are proposed by the developed integrated processing:
bulk performances: stiffness and strength, damping
surface performances: surface protection, surface finish, tribological properties
shape performances: continuous or discontinuous shape
function performances: temperature shielding, close tolerances, multi-functionality.

Process for the manufacture of polymer and composite products

Ecole Polytechnique Federale de Lausanne


A mobile measuring device (100) includes a power supply module (110) that includes a rechargeable battery (120), a primary battery (130) and an electronic control unit (140). The rechargeable battery is permanently installed in the mobile measuring device and can be charged via a charging device (122) of the mobile measuring device. The primary battery is also permanently installed in the mobile measuring device. The electronic control unit is configured to guarantee a power supply of the mobile measuring device via the rechargeable battery as long as an electrical minimum power supply is provided by the rechargeable battery and to change to a temporary power supply by the primary battery if the minimum supply power is undershot.

Using a rechargeable battery or primary battery for the power supply of a mobile measuring device is generally known. A rechargeable battery has the advantage that it can, in principle, be charged, whereas a primary battery cannot be reused after the power stored in it is used up.
Moreover, the use of an electronic control unit, by means of which it is possible to change between different power supply devices, is known.
Thus, EP 3 333 008 A1 describes an adaptive system for the management of a plurality of battery cells, which are connected to one another in a common circuit. In this case, the circuit changes the power supply between the plurality of battery cells as a function of a determined state of each of the battery cells.

Mobile measuring device with a power supply module and process for power supply


A land grid array connector assembly (1) comprises a socket (11) and a fastening device (10) surrounding the socket. The fastening device includes an insulative frame (13), a lever (12) and a metal clip (14) respectively assembled to a first and a second side of the frame. The lever is pivotally assembled to the first side of the frame, the clip is movably mounted to the second side of the frame, and the clip has a pair of acting portions (141) respectively received in a pair of locating grooves (15) of the frame. Each locating groove has a horizontal portion (151) and an arced portion (152) connected with the horizontal portion. The acting portion rotates in the arced portions of the locating grooves and slides in horizontal portions of the locating grooves.

1. Field of the Invention
The present invention relates to the art of electrical connectors, and more particularly to a land grid array connector assembly having a fastening device for securing a central processing unit (CPU) therein.
2. Description of the Prior Art
A conventional land grid array connector assembly 6, as shown in FIG. 8, commonly includes a fastening device 60 and a socket 61 received in the device 60. The fastening device 60 comprises a quadrate frame 63, a lever 62 and a metal clip 64 respectively mounted to opposite sides of the frame 63. The frame defines a pair of locating slots 66 at one side thereof and a pair of guiding grooves 65 at another opposite side thereof. Each guiding groove 65 has a first inner wall 651 and a second inner wall 652. The lever 62 has a pair of locating portions 623 pivotally positioned in locating slots 66 of the frame 63, a driving portion 621 defined between the locating portions 623, and a handling portion 622 bending vertically from one of the locating portions 623. The clip 64 has a pair of securing portion 641 movably received in the guiding grooves 65 of the frame 63 and a driving hook 644 defined at a free end thereof.
In use, the clip 64 is firstly set up perpendicular to the frame 63 with the securing portion 641 pressing close to the first inner walls 651 of the guiding grooves 65, a CPU 7, together with a copper plate 8 which functions as a heat dissipation device, is assembled on the socket 61. Then, the clip 64 is rotated to a parallel position and abuts against the copper plate 8. However, as can be seen from FIG. 9, during the rotation of the clip 64, the clip 64 may simultaneously move along the guiding grooves 65 towards the second inner wall 652 which leads to the driving hook 644 of the clip 64 extending beyond its correct position. As a result, when rotating the handling portion 622 of the lever 62, the driving portion 621 of the lever 62 cannot slide into the driving hook 644 of the clip 64 and drive it, which leads to the clip 64 can not reach its final pressing position. Thus, the clip 64 fails to locate the CPU 7 and the copper plate 8 securely.
Accordingly, an object of the present invention is to provide a land grid array connector assembly having a fastening device for retaining a central processing unit (CPU) securely in the connector assembly.
Another object of the present invention is to provide a fastening device for a land grid array socket to fasten a CPU in the land grid array socket.
In order to achieve the objects set forth, a land grid array connector assembly in accordance with the present invention includes a socket and a fastening device surrounding the socket. The fastening device comprises a frame having a first side and a second side opposite to the first side, a lever pivotally mounted to the first side of the frame, and a metal clip movably mounted to the second side of the frame.
The frame includes a pair of locating slots defined at opposite ends of the first side and a pair of locating grooves defined at opposite ends of the second side, each locating groove has a horizontal portion and an arced portion connected with the horizontal portion. The lever has a pair of locating portions received in the locating slots, a driving portions defined between the locating portions, and a handling portion bending vertically from one of the locating portions. The clip has a pair of acting portions respectively received in the locating grooves and a driving hook defined at a free end thereof. The acting portions of the clip can only rotate in the arced portions of the locating grooves when the clip rotates from a vertical position to a horizontal position and can only slide in the horizontal portions of the locating grooves when the driving portion of the lever drives the driving hook of the clip.


The present invention provides an antigenic composition, the composition comprising at least one recombinant protein. The recombinant protein comprises at least one epitope. The epitope is reactive with an antibody which is reactive with a polypeptide having the sequence set out in SEQ. ID. NO. 3 or SEQ. ID. NO. 5. The invention also provides methods and compositions for the production of the recombinant protein. Also provided are methods for the diagnosis, treatment and prevention of P. gingivalis infection.

This invention relates generally to recombinant proteins of Porphyromonas gingivalis, r-RgpA44 and r-Kgp39. The invention also relates to pharmaceutical compositions and associated agents based on these recombinant proteins and derivatives for the detection, prevention and treatment of periodontal disease associated with P. gingivalis.
Periodontal diseases are bacterial-associated inflammatory diseases of the supporting tissues of the teeth and range from the relatively mild form of gingivitis, the non-specific, reversible inflammation of gingival tissue to the more aggressive forms of periodontitis which are characterised by the destruction of the tooth's supporting structures. Periodontitis is associated with a subgingival infection of a consortium of specific Gram-negative bacteria that leads to the destruction of the periodontium and is a major public health problem. One bacterium that has attracted considerable interest is P. gingivalis as the recovery of this microorganism from adult periodontitis lesions can be up to 50% of the subgingival anaerobically cultivable flora, whereas P. gingivalis is rarely recovered, and then in low numbers, from healthy sites. A proportional increase in the level of P. gingivalis in subgingival plaque has been associated with an increased severity of periodontitis and eradication of the microorganism from the cultivable subgingival microbial population is accompanied by resolution of the disease. The progression of periodontitis lesions in non-human primates has been demonstrated with the subgingival implantation of P. gingivalis. These findings in both animals and humans suggest a major role for P. gingivalis in the development of adult periodontitis.
More recently there has been increasing linkage of priodontal disease and cardiovascular disease and therefore a link between P. gingivalis infection and cardiovascular disease. More information regarding this linkage can be found in Beck, J D et al. Ann Periodontol. 3: 127-141, 1998 and Beck, J. et al. J. Periodontol. 67:1123-37, 1996.
P. gingivalis expresses a range of proteins on its cell surface that are potential candidates for the development of a vaccine or diagnostic. A major group of cell surface proteins expressed by P. gingivalis is a group of proteinases and associated adhesins. One proteinase designated Arg-gingipain has been disclosed previously by Travis et al. (PCT Publication No. WO 95/07286). These investigators also reported a high molecular mass form of Arg-gingipain that is encoded by the gene rgp also disclosed in WO 95/07286. The high molecular mass form of Arg-gingipain consists of the proteinase and several other proteins proposed to be adhesins. Cell-surface complexes of P. gingivalis consisting of Arg- and Lys-specific proteinases and adhesins have also been disclosed by Reynolds et al. (PCT/AU96/00673). Neither of these disclosures provide teaching regarding the utility of a particular adhesin as a recombinant in the protection of P. gingivalis infection.


A respiratory sound analyzer system for use in the noisy ambient environments, such as in medical transport vehicles including helicopters, boats, aircraft, ambulances, and other vehicles, as well as at fire scenes, disasters, sporting events, rock concerts, and the like, includes an array of miniature accelerometers which are connected to the chest of a patient. Rather than relying on traditional auscultation, the on-board personnel will analyze a conditioned signal on a display screen or other device to monitor a patient's breathing patterns. Successive signals may be stored and compared with each other to determine a deterioration in a patient's breathing pattern, and signals may also be compared with stored normal and abnormal breathing signals. Ambient noise effects can be reduced or eliminated from the sensed breathing signal by a number of means. For example, the accelerometers can be heavily padded to deaden impinging sound waves, signals from accelerometers placed on the patient at locations where respiratory sounds will not be detected can be subtracted from the signals from accelerometers on the patient's chest, and filters can be used to isolate breath sounds from ambient noises.

1. Field of the Invention
The present invention generally relates to devices used to detect and analyze respiratory sounds. More particularly, the invention is directed to a device used for the identification and monitoring of a parent's breathing patterns in a noisy ambient environment such as in a medical transport helicopter, aircraft, boat, ambulance, or other vehicle, or at a fire, disaster, sporting event, rock concert, or the like.
2. Description of the Prior Art
Traditional auscultation (i.e., listening) is an unacceptable method for monitoring the breathing patterns of a patient in a noisy ambient environment such as a medical transport helicopter or an ambulance. In short, experience with stethoscopes, amplified stethoscopes, and other listening devices has shown that even trained personnel are not able to distinguish respiratory sounds of a patient when the patient is located in a noisy ambient environment.
Cottrell et al., JAMA, 262:1653-1656 (1989), reported that during a one year study of medical emergencies on a commercial airline, the stethoscope was used in 80% of the instances when the on-board medical kit was required. However, a later letter to the Editor of JAMA by Bishop, JAMA, 263:233 (1990), and a reply by Cottrell and Kohn, JAMA, 263:233 (1990), indicated that in-flight auscultation attempts were unsuccessful due to the amount of ambient noise in the aircraft cabin. Cottrell and Kohn noted that ambient noise levels on board a commercial aircraft generally are low frequency, range upward to 65 dB [sic] and may approach 90 dB. They state that "At these levels, any worthwhile auscultation may be impossible, regardless of stethoscope type".
Hunt et al., JAMA, 265:1992-1994 (1991), reported that in no instances of in-flight experimental listening to recorded breath sounds emanating from the chest cavity of a resuscitation training manikin were medical personnel able to determine whether or not any breath sounds were present. This was true whether the in-flight nurses used conventional or amplified stethoscopes. Hunt et al. concluded that "Further research to develop new methods of breath sound assessment during air medical transport is urgently needed and will require the cooperative efforts of audiologists, engineers, air medical transport professionals, and physicians".
Similar poor results with stethoscopes were reported in Shenai, "Sound levels for neonates in transit", J. Pediat., 90:811-812 (1977).
Medical emergencies occur in a wide range of situations. Often, attending physicians or other medical emergency personnel must begin treatment of patients in less than ideal situaffons where ambient noise can impair the ability to detect audible respiratory sounds. Because breathing is a basic requirement of life itself, and often needs to be monitored in many medical emergencies, it would be advantageous to have equipment which allows for accurate detection and monitoring of a patient's breathing patterns. The above articles clearly indicate that present techniques of using stethoscopes is unsuitable. There is a need for an alternative device for detecting breathing signals.

Respiratory sound analyzer for use in high noise environments