A receiver uses a transmission channel matrix to obtain a superior signal separation characteristic regardless of differences in levels of multipath signals. A multipath linear combining unit performs linear combining of the multipaths in received signals of the reception antennas by means of the transmission channel matrix between the plurality of transmission antennas and the plurality of reception antennas. A maximum likelihood detector compares signals in which multipaths have been combined by the multipath linear combining unit with reception replicas that have been found using the transmission channel matrix to estimate the transmitted signals of each of the transmission antennas.

1. Field of the Invention
The present invention relates to a receiver, a receiving method, and a radio communication system that are used in communication realized by MIMO, and more particularly to a receiver, a receiving method, and a radio communication system in which MIMO signals are demodulated by means of maximum likelihood detection (MLD) from signals that are received using a plurality of reception antennas.
2. Description of the Related Art
Radio communication methods in next-generation mobile communication demand high-speed data transmission. MIMO (Multiple Input Multiple Output) multiplexing is receiving attention as a technology for realizing high-speed data transmission. MIMO is a technology for transmitting a plurality of signals from a plurality of transmission antennas at the same frequency and the same time, receiving these signals using a plurality of reception antennas, and then demodulating (implementing signal separation of) the plurality of signals.
FIG. 1 is a block diagram showing the configuration of a typical radio communication system that uses MIMO. In this case, the number of transmission antennas is M (where M is an integer equal to or greater than 1), and the number of reception antennas is N (where N is an integer equal to or greater than 1).
Referring to FIG. 1, the radio communication system includes transmitter 81 and receiver 82. Transmitter 81 has a plurality of transmission antennas 831-83M, and receiver 82 has a plurality of reception antennas 841-84N.
Transmitter 81 transmits differing signals from each of a plurality of transmission antennas 831-83M at the same time and at the same frequency. Receiver 82 uses a plurality of reception antennas 841-84N to receive the signals that have been transmitted from transmitter 81 and, from these received signals, demodulates M signals by means of a signal separation process. According to this radio communication system, increasing the number of signals that are simultaneously transmitted and received in proportion to the number of transmission antennas enables the realization of high-speed data transmission without increasing the transmission bandwidth.
On the other hand, DS-CDMA (Direct Sequence-Code Division Multiple Access) is widely used as a mobile communication radio access method.
In DS-CDMA, time-spreading a transmission signal by a particular code can effectively reduce the interference of other cells in a multi-cell environment and enable one-cell repetition. In addition, separating multipath signals by means of despreading and then combining these multipath signals (rake combining) can obtain the path diversity effect.
In recent years, the possibility of enabling even higher-speed data transmission through the application of MIMO multiplexing to DS-CDMA (CDMA MIMO multiplexing) is being investigated. Various methods have been proposed as the signal separation process in CDMA MIMO multiplexing, examples including: Minimum Mean Square Error (MMSE), Vertical Bell Labs Layered Space-Time (VBLAST), and Maximum Likelihood Detection (MLD).
MMSE is a method in which interference from transmission antennas other than the target transmission antenna are suppressed by a linear filter. VBLAST is a method in which MMSE and successive interference cancellation of transmission antenna signals are repeated (for example, refer to A. Adjoudani, E. C. Beck, A. P. Burg, G. M. Djuknic, T. G. Gvoth, D. Haessig, S. Manji, M. A. Milbrodt. M. Rupp, D. Samardzija, A. B. Siegel, T. Sizer, H. C. Tran, S. Walker, S. A. Wilkus, and P. W. Wolnianski, "Prototype Experience for MIMO BLAST over Third-Generation Wireless System," IEEE J. Select. Areas Commun., Vol. 21, no. 3, pp. 440-451, April 2003 (Document 1)). MLD is a method of generating replicas of all transmission antenna signals and using these replicas to select the most likely transmission antenna signal.
MLD has superior characteristics to MMSE and VBLAST but has the disadvantage that the increase in the number of transmission antennas and the number of modulation multivalues brings with it an exponential increase in computation load. As a solution to this drawback, a reduced-computation-load MLD is now being investigated that can greatly reduce the MLD computation load.
One example of a prior-art MIMO receiver that uses MLD to perform a CDMA MIMO signal separation process is next shown. FIG. 2 is a block diagram showing the configuration of a MIMO receiver of the prior art. In this case, the number of transmission antennas provided in a transmitter (not shown) is M (where M is an integer equal to or greater than 1), and the number of reception antennas is N (where N is an integer equal to or greater than 1).
Referring to FIG. 2, the MIMO receiver of the prior art includes: reception antennas 911-91N, despreaders 9211-921L, . . . 92N1-92NL, transmission channel estimation unit 93, and MLD unit 94.
Each of despreaders 9211-921L despreads a respective path of each signal that is received at reception antenna 911. Similarly, the received signals of each of the reception antennas are despread for each path by L despreaders, each of despreaders 92N1-92NL despreading the signal received by reception antenna 91N for a respective path. The despread signals that are obtained as a result are provided to MLD unit 94.
In this case, if yn, l is the despread symbol of path l of reception antenna n, despread symbol vector y can be shown as shown in Equation (1).y=[y0,0 . . . y0,L-1y1,0 . . . yN-1,L-1]T  (1)
Transmission channel estimation unit 93 receives as input the signals that have been received at reception antennas 911-91N, uses a known pilot signal that is included in these received signals to estimate for each path the transmission channel estimation value between the transmission and reception antennas. If the transmission channel estimation value of path l between transmission antenna m and reception antenna n is hm, n, l, then transmission channel matrix H can be represented by (N×L) rows and M columns as seen in Equation (2).
                    H        =                  [                                                                      h                                      0                    ,                    0                    ,                    0                                                                                h                                      1                    ,                    0                    ,                    0                                                                              …                                                              h                                                            M                      -                      1                                        ,                    0                    ,                    0                                                                                ⋮                                            ⋮                                            ⋱                                            ⋮                                                                                h                                      0                    ,                    0                    ,                                          L                      -                      1                                                                                h                                      1                    ,                    0                    ,                                          L                      -                      1                                                                                …                                                              h                                                            M                      -                      1                                        ,                    0                    ,                                          L                      -                      1                                                                                h                                      0                    ,                    1                    ,                    0                                                                                h                                      1                    ,                    1                    ,                    0                                                                              …                                                              h                                                            M                      -                      1                                        ,                    1                    ,                    0                                                                                ⋮                                            ⋮                                            ⋱                                            ⋮                                                                                h                                      0                    ,                                          N                      -                      1                                        ,                                          L                      -                      1                                                                                h                                      1                    ,                                          N                      -                      1                                        ,                                          L                      -                      1                                                                                …                                                              h                                                            M                      -                      1                                        ,                                          N                      -                      1                                        ,                                          L                      -                      1                                                                                ]                                    (        2        )
MLD unit 94 uses transmission channel matrix H that is obtained by transmission channel estimation unit 93 to generate reception replicas for the signals that have been received from all transmission antennas, calculates the error signals between the despread signals from each of despreaders 9211-92NL and the reception replicas, and selects the transmission antenna signal that is most likely.
If the transmission symbol vector s is shown in Equation (3), and noise vector n is shown in Equation (4), transmission channel matrix H can be used to represent despread symbol vector y as shown in Equation (5):
                    s        =                              [                                                                                s                    0                                                                                s                    1                                                                    …                                                                      s                                          M                      -                      1                                                                                ]                    T                                    (        3        )                                n        =                              [                                                                                n                                          0                      ,                      0                                                                                …                                                                      n                                          0                      ,                                              L                        -                        1                                                                                n                                          1                      ,                      0                                                                                …                                                                      n                                                                  N                        -                        1                                            ,                                              L                        -                        1                                                                                ]                    T                                    (        4        )                                y        =                  Hs          +          n                                    (        5        )
In Equation (3), sm shows the transmission symbol of transmission antenna m. In Equation (4), nn, l shows the noise in path l of reception antenna n.
FIG. 3 is a block diagram showing the configuration of MLD unit 94. Referring to FIG. 3, MLD unit 94 includes: transmission symbol candidate generation unit 941, reception replica generation unit 942, error signal calculation unit 943, and bit likelihood calculation unit 944.
Transmission symbol candidate generation unit 941 generates transmission symbol vector s, which is the combination of all transmission antenna symbols, and sends this transmission symbol vector to reception replica generation unit 942.
Reception replica generation unit 942 generates all reception replicas {tilde over (r)}=Hs based on transmission symbol vector s from transmission symbol candidate generation unit 941 and transmission channel matrix H, and sends these transmission replicas to error signal calculation unit 943.
Error signal calculation unit 943 finds the final error signal  based on reception replicas {tilde over (r)} from reception replica generation unit 942 and despread symbols y from despreaders 9211-92NL, and sends this error signal  to bit likelihood calculation unit 944. At this time, error signal calculation unit 943 compares reception replica {tilde over ( )}rn, l and despread symbol yn, l as shown in Equation (6), and then adds each of the error signals as shown in Equation (7) to find the final error signal .
                                          [                                                                                y                                          0                      ,                      0                                                                                ⋮                                                                                y                                          0                      ,                                              L                        -                        1                                                                                y                                          1                      ,                      0                                                                                ⋮                                                                                y                                                                  N                        -                        1                                            ,                                              L                        -                        1                                                                                ]                                                                                ⇔                                                                              ⇔                                                                              ⋮                                                                              ⇔                                                                                [                                                                                r                        ~                                                                    0                        ,                        0                                                                                ⋮                                                                                r                        ~                                                                    0                        ,                                                  L                          -                          1                                                                                r                        ~                                                                    1                        ,                        0                                                                                ⋮                                                                                r                        ~                                                                                N                          -                          1                                                ,                                                  L                          -                          1                                                                                ]                                      =                  H                                [                                                                                s                    0                                                                                s                    1                                                                                ⋮                                                                                s                                          M                      -                      1                                                                                ]                                              (        6        )                                Λ        =                              ∑                          n              =              0                                      N              -              1                                                                    ∑                              l                =                0                                            L                -                1                                                                                                                                      y                                          n                      ,                      l                                                        -                                                            r                      ~                                                              n                      ,                      l                                                                                                  2                                                          (        7        )
Bit likelihood calculation unit 944 receives as input error signals  that correspond to all transmission antenna symbols s and calculates the likelihood for each bit that is transmitted from each transmission antenna. At this time, bit likelihood calculation unit 944 applies the bit likelihood as input to error correction decoder (not shown) (for example, turbo decoder) and restores the information bit sequence. One method for calculating bit likelihood is based on the difference between the minimum error signal of the symbol in which the target bit is +1 and the minimum error signal of the symbol in which the target bit is −1, as described in N. Maeda, K. Higuchi, J. Kawamoto, M. Sawahashi, M. Kimata, and S. Yoshida, "QRM-MLD Combined with MMSE-Based Multipath Interference Canceller for MIMO Multiplexing in Broadband DS-CDMA" (Proc. IEEE PIMRC 2004, pp. 1741-1746, September 2004 (Document 2)).
FIG. 4 is a block diagram showing the configuration of another MIMO receiver of the prior art. The MIMO receiver shown in FIG. 4 has a greatly decreased amount of MLD calculation compared to the device shown in FIG. 2 (see Document 2).
Referring to FIG. 4, the MIMO receiver of the prior art includes: reception antennas 911-91N; despreaders 9211-921L, . . . , 92N1-92NL; transmission channel estimation unit 93; QR decomposition unit 95, QH converter 96; and reduced-calculation-load MLD unit 97.
Reception antennas 911-91N, despreaders 9211-921L, . . . , 92N1-92NL, and transmission channel estimation unit 93 each have the same configuration as FIG. 2.
QR decomposition unit 95 decomposes the transmission channel matrix H that is obtained in transmission channel estimation unit 93 into the product of the Q matrix and R matrix as shown in Equation (8), sends Q to QH converter 96, and sends R to reduced-calculation-load MLD unit 97.
                                                        H              =                                          QR                                                                          =                                                          [                                                                                q                                                  0                          ,                                                                                0                          ,                                                                                0                                                                                q                                                  1                          ,                                                                                0                          ,                                                                                0                                                                                …                                                                                q                                                                              M                                                                                -                                                                                1                                                    ,                                                                                0                          ,                                                                                0                                                                                ⋮                                                              ⋮                                                              ⋱                                                              ⋮                                                                                q                                                  0                          ,                                                                                0                          ,                                                                                L                                                                                -                                                                                1                                                                                q                                                  1                          ,                                                                                0                          ,                                                                                L                                                                                -                                                                                1                                                                                …                                                                                q                                                                              M                                                                                -                                                                                1                                                    ,                                                                                0                          ,                                                                                L                                                                                -                                                                                1                                                                                q                                                  0                          ,                                                                                1                          ,                                                                                0                                                                                q                                                  1                          ,                                                                                1                          ,                                                                                0                                                                                …                                                                                q                                                                              M                                                                                -                                                                                1                                                    ,                                                                                1                          ,                                                                                0                                                                                ⋮                                                              ⋮                                                              ⋱                                                              ⋮                                                                                q                                                  0                          ,                                                                                N                                                                                -                                                                                1                                                    ,                                                                                L                                                                                -                                                                                1                                                                                q                                                  1                          ,                                                                                N                                                                                -                                                                                1                                                    ,                                                                                L                                                                                -                                                                                1                                                                                …                                                                                q                                                                              M                                                                                -                                                                                1                                                    ,                                                                                N                                                                                -                                                                                1                                                    ,                                                                                L                                                                                -                                                                                1                                                                                ]                                                                                [                                                                                r                                                  0                          ,                                                                                0                                                                                r                                                  0                          ,                                                                                1                                                                                …                                                                                r                                                  0                          ,                                                                                M                                                                                -                                                                                1                                                                                0                                                                                r                                                  1                          ,                                                                                1                                                                                …                                                                                r                                                  1                          ,                                                                                M                                                                                -                                                                                1                                                                                ⋮                                                              0                                                              ⋱                                                              ⋮                                                                                0                                                              …                                                              0                                                                                r                                                                              M                                                                                -                                                                                1                                                    ,                                                                                M                                                                                -                                                                                1                                                                                ]                                                                        (        8        )
In this case, Q is a unitary matrix of (N×L) rows and M column, each column vector being orthogonal (QHQ=1), and the norm is 1. R is an upper triangular matrix of M rows and M columns.
QH converter 96 multiplies despread symbol vector y with QH to convert y to an orthogonal coordinate system represented by Q. QH converter 96 is of a configuration for realizing computation for multiplying QH by multipliers and adders. Signal vector z after coordinate conversion is represented by Equation (9).
                                                        z              =                                                                            Q                  H                                                y                                                                                =                                                          [                                                                                z                        0                                                                                z                        1                                                                                ⋮                                                                                z                                                  M                          -                          1                                                                                ]                                                                                =                                                          [                                                                                q                                                  0                          ,                                                                                0                          ,                                                                                0                                                *                                                                                …                                                                                q                                                  0                          ,                                                                                0                          ,                                                                                L                                                                                -                                                                                1                                                                          *                                                                                q                                                  0                          ,                                                                                1                          ,                                                                                0                                                *                                                                                …                                                                                q                                                  0                          ,                                                                                N                                                                                -                                                                                1                                                    ,                                                                                L                                                                                -                                                                                1                                                                          *                                                                                q                                                  1                          ,                                                                                0                          ,                                                                                0                                                *                                                                                …                                                                                q                                                  1                          ,                                                                                0                          ,                                                                                L                                                                                -                                                                                1                                                                          *                                                                                q                                                  1                          ,                                                                                1                          ,                                                                                0                                                *                                                                                …                                                                                q                                                  1                          ,                                                                                N                                                                                -                                                                                1                                                    ,                                                                                L                                                                                -                                                                                1                                                                          *                                                                                ⋮                                                              ⋱                                                              ⋮                                                              ⋮                                                              ⋱                                                              ⋮                                                                                q                                                                              M                                                                                -                                                                                1                                                    ,                                                                                0                          ,                                                                                0                                                *                                                                                …                                                                                q                                                                              M                                                                                -                                                                                1                                                    ,                                                                                0                          ,                                                                                L                                                                                -                                                                                1                                                                          *                                                                                q                                                                              M                                                                                -                                                                                1                                                    ,                                                                                1                          ,                                                                                0                                                *                                                                                …                                                                                q                                                                              M                                                                                -                                                                                1                                                    ,                                                                                N                                                                                -                                                                                1                                                    ,                                                                                L                                                                                -                                                                                1                                                                          *                                                                                ]                                                                                [                                                                                y                                                  0                          ,                          0                                                                                ⋮                                                                                y                                                  0                          ,                                                      L                            -                            1                                                                                y                                                  1                          ,                          0                                                                                ⋮                                                                                y                                                                              N                            -                            1                                                    ,                                                      L                            -                            1                                                                                ]                                                                                =                                                                            Q                  H                                                                  (                                      Hs                    +                    n                                    )                                                                                =                                                                            Q                  H                                                                  (                                      QRs                    +                    n                                    )                                                                                =                                                                                Q                    H                                                      QRs                                +                                                      Q                    H                                                      n                                                                                =                                                          Rs                +                                                      Q                    H                                                      n                                                                                =                                                          Rs                +                                  n                  ′                                                                                (        9        )
In this case, noise n′ is noise n projected onto an orthogonal coordinate system represented by Q, and therefore uncorrelated with n at the same power.
Reduced-calculation-load MLD unit 97 uses the R matrix from QR decomposition unit 95 to generate reception replicas for the signals of all transmission antennas, calculates the error signals between the reception replicas and the signal vector z following coordinate conversion, and after cutting back symbol candidates, selects the most likely transmission antenna signal.
FIG. 5 is a block diagram showing the configuration of reduced-calculation-load MLD unit 97. Referring to FIG. 5, reduced-calculation-load MLD unit 97 includes: transmission symbol candidate generation unit 971, reception replica generation unit 972, error signal calculation/symbol candidate reduction unit 973, and bit likelihood calculation unit 974.
As with transmission symbol candidate generation unit 941 of FIG. 3, transmission symbol candidate generation unit 971 generates transmission symbol vector s, which is the combination of all transmission antenna symbols, and sends transmission symbol vector s to reception replica generation unit 972.
Reception replica generation unit 972 generates all reception replicas {tilde over (r)}=Rs from transmission symbol vector s from transmission symbol candidate generation unit 971 and matrix R from QR decomposition unit 95 and sends the reception replicas to error signal calculation/symbol candidate reduction unit 973.
Error signal calculation/symbol candidate reduction unit 973 reduces symbol candidates while finding error signal m from reception replicas {tilde over (r)}m and signal vector zm following coordinate conversion by QH converter 96 over a plurality of stages for the plurality of transmission antennas.
As an example, the reduction of symbol candidates is carried out successively starting from the largest transmission antenna number.
In each stage of the reduction of symbol candidates, error signal calculation/symbol candidate reduction unit 973 compares reception replicas {tilde over (r)}m and signal vectors zm as shown in Equation (10), and finds error signal m as shown in Equation (11). Error signal calculation/symbol candidate reduction unit 973 further reduces symbol candidates by selecting only a prescribed number from the symbol candidates having low error signals m.
                                          [                                                                                z                    0                                                                                z                    1                                                                                ⋮                                                                                z                                          M                      -                      1                                                                                ]                                                                                ⇔                                                                                ⇔                                                                                ⋮                                                                                ⇔                                                                                [                                                                                r                                    ~                                                                    0                                                                                r                                    ~                                                                    1                                                                                ⋮                                                                                r                        ~                                                                    M                        -                        1                                                                                ]                                      =                  R                                [                                                                                s                                0                                                                                s                                1                                                                                ⋮                                                                                s                                          M                      -                      1                                                                                ]                                              (        10        )                                          Λ          m                =                              ∑                          i              =              m                                      M              -              1                                                                                                                    z                  i                                -                                                      r                    ~                                    i                                                                    2                                              (        11        )
Bit likelihood calculation unit 974 calculates the likelihood for each bit that is transmitted from each transmission antenna based on the error signals  that correspond to all transmission antenna symbols s that have been finally eliminated.
Nevertheless, the above-described prior art has the following drawbacks.
The MIMO receiver of the prior art shown in FIG. 2 compares the reception replicas that are generated using the transmission channel estimation values of each path with the multipath signals that are separated in despreading to perform a signal separation process by MLD. At this time, the differences in levels of the multipath signals is not taken into consideration, and as a result, when there are differences in the levels of each multipath signal, the multipath interference sustained by each path differs, multipaths having a low level receiving the greatest multipath interference. In a MIMO receiver of the prior art, the influence of multipath interference is not taken into consideration in the calculation of error signals, and as a result, there is a disproportionately large addition of the error signal of multipaths having a low level and a consequent degradation of the signal separation characteristic.
On the other hand, the other MIMO receiver of the prior art shown in FIG. 4, performs the MLD process using signals in which despread signals undergo QH conversion, but because the transmission channel matrix is subjected to direct QR decomposition, the operation is principally equivalent to that of the MIMO receiver of FIG. 2, and is therefore subject to the same problem.

Radio communication system that uses a MIMO receiver


Method to determine the viscosity of a water-in-oil emulsion that will be formed by an oil comprising organic acids when mixed with water comprising:

Removal of corrosive water-soluble salts, particularly chlorides of sodium and potassium from crude oil is an important processing operation in refining of crude oils. The process of desalting usually involves addition of 1 to 20 weight percent wash water to the crude oil with mixing to form a water-in-crude oil emulsion. Then, the water-in-crude oil emulsion is subjected to electrostatic demulsification or hydrocyclone treatment. Under the influence of electrostatic or centrifugal fields the dispersed water droplets coalesce and the water-in-oil emulsion is demulsified. Thereafter, the water containing water soluble salts is separated from the crude oil.
Most heavy crude oils contain asphaltenes and naphthenic acids and tend to form stable high viscosity water-in-oil emulsions. Both, the stability and the high viscosity of the water-in-oil emulsions present difficulties in demulsification. Inefficient demulsification results in inefficient dewatering and desalting of the heavy crude oils. Large volumes of a rag layer tend to form in the separator vessels and result in substantial oil loss during dewatering and desalting processes. Current methods using centrifuges, hydrocyclones and electrostatic demulsifiers require large doses of demulsifier chemicals to destabilize the water-in-oil emulsions. High emulsion viscosity requires higher than normal operation temperatures and longer residence times for desalting and/or dewatering these water-in-oil emulsions in the separator vessels. Thus, there is a continuing need for improved cost-effective methods to dewater and desalt water-in-oil emulsions especially those formed from heavy crude oils. In particular there is a need to determine the viscosity of water in-oil emulsions formed from heavy crude oils using heavy oil composition data prior to desalting and dewatering operations so that the operating conditions of the separator vessels can be adjusted prior to dewatering and desalting. There is also a need for improved methods to form low viscosity water-in-oil emulsions for a variety of applications. Such applications include low viscosity lubricant fluids and low viscosity pusher fluids for improved oil recovery. The present invention addresses these needs. In particular, hydrocarbon oils that contain asphaltenes and naphthenic acids, such as crude oils, tend to form water-in-oil emulsions with a wide range of viscosity.

Method for determining viscosity of water-in-oil emulsions

Abstract: determining the value of the expression:

Abstract: η          (      emul      )        =            K                                              η                  (          oil          )                                  TAN                  -          r                                    (                  1          -          ϕ                )            2.5      wherein η(oil) is the viscosity the oil, TAN is the total acid number of the oil, φ is a number in the range of 0.1 to 0.8, r is a number in the range of about 0.5 to 2, and K is a number from about 1 to 20, said determined value, η(emul) being the viscosity of the water-in-oil emulsion.

Abstract: The method is used to prepare water-in-oil emulsions of predetermined viscosity and to improve desalting of oils.

ExxonMobil Research and Engineering Company


A method for therapeutic or prophylactic control of Acquired Immunodeficiency Syndrome (AIDS) in which an effective dose of phosphonoformic acid or a therapeutically-acceptable salt thereof is administered to a patent.

The present invention relates to a method for the therapeutical and prophylactic control and treatment of acquired immunodeficiency syndrome (AIDS).
In the late seventies a new disease was reported, which subsequently was referred to as Acquired Immuno Deficiency Syndrom (AIDS). It is now generally accepted that a retrovirus referred to as Human T-cell Leukemia Virus (HTLV-III) or Lymphadenopathy Associated Virus (LAV) plays an essential role in the etiology of AIDS. This virus will herebelow be denoted HTLV-III.
The full-blown AIDS is characterized by a profound immunodeficiency due to low numbers of a subset of lymphocytes-T-helper cells, which are the targets for HTLV-III lytic infections. The profound immunodeficiency, in the full-blown AIDS patients makes these patients highly susceptible to a variety of opportunistic infections of bacterial, fungal, protozoal or viral etiology. The etiological agents among viral opportunistic infections are often found in the herpes virus group, i.e., Herpes Simplex virus (HSV), Varicella Zoster virus (VZV), Epstein-Barr virus (EBV) and especially cytomegalo virus(CMV).
The discovery of HTLV-III as the likely cause of AIDS has presented a possible target for chemotherapy.

Method for the control and treatment of acquired immunodeficiency syndrome (AIDS)


A method for controlling a laundry washing machine. The method includes: performing a tub loading process comprising operating supply valve(s) to provide a first volume of water through a detergent supply system and into a tub to fill the tub with wash liquid; performing a washing process comprising rotating a drum to agitate laundry in in the presence of the wash liquid; performing a static rinsing process comprising operating a pump to remove any free volume of wash liquid from the tub without rotating the drum; and performing one or more rinsing processes comprising: operating the supply valve(s) to provide a volume of clean rinse water to the tub, operating the pump to remove the rinse water from the drum, and operating the motor to spin the drum at high speed to extract rinse water from the laundry, while continuing to operate the pump.

The use of automated laundry washing machines is widespread. Such machines include both relatively simple laundry washing machines that can only wash and rinse laundry, and more complex laundry washing machines that can also dry laundry. The term "laundry washing machine" is used herein to refer to both types of laundry washing machine, and other laundry washing machines as may be known or later made available.
Laundry washing machines typically use a liquid solution to help remove soil from fabrics. The liquid solution usually is water-based, and may comprise water alone, or water mixed with additives (e.g., detergent, fabric softener, bleach, etc.). The cleaning solution may be provided at a variety of different temperatures.
A laundry washing machine typically includes a tub configured to receive and hold the cleaning solution and a drum rotatably mounted inside the tub to receive and hold fabric laundry products, such as clothing, bed sheets and other linens, curtains, and the like. The drum is perforated or otherwise configured to allow cleaning solution to pass between the tub and the drum. In "front-loading" washing machines, the drum rotates on a horizontal or nearly horizontal axis, and the cleaning solution is provided in the lower end of the tub, and as the drum rotates, the laundry is repeatedly raised and lowered into an out of the cleaning solution. In "top-loading" washing machines, the drum rotates on a vertical or nearly vertical axis, and the cleaning solution is provided, during the wash phase, at a level that the laundry is immersed within the solution. The drum may be reciprocated back and forth to agitate the laundry and cleaning solution, or the drum may remain still while a separate agitator located inside the drum moves to perform the agitation.
The laundry washing machine may have a number of operation programs, which may be selected by the user or selected automatically based on detected conditions (e.g., load weight). In a typical wash phase, the laundry washing machine may determine the amount of wash water and rinse water according to a user's selection of a particular washing program, and then proceed to supply the appropriate amount of cleaning solution to the tub, operate the drum, and otherwise control the laundry washing machine components to execute the selected washing program.
At the end of the wash phase, the laundry washing machine typically performs one or more intermediate spin cycles during which the drum is rotated at a high speed one or more times for extracting the cleaning solution from the laundry. The cleaning solution is drained from the washing tub by activating a draining pump before, during and/or after one or more of these intermediate spin cycles.
Next, the washing machine typically starts a rinse phase in which a suitable amount of clean water is provided to the tub to rinse any remaining cleaning solution from the laundry, and the drum (and/or agitator) is rotated to help dilute and remove the remaining cleaning solution.
At the end of the rinse phase, the laundry washing machine typically performs one or more final spin cycles to remove the water and any diluted cleaning solution from the laundry. The water and diluted cleaning solution may be drained before, during and/or after one or more of the final spin cycles by operating the draining pump.
A typical laundry washing machine includes an electronic control system that is configured to perform the foregoing operations and other operations. The control system may include various user control inputs, logical programming to perform one or more operation programs, sensor feedback systems, and so on.
One typical optional operation program is a program intended to address the presence of a large amount of dirt in the laundry. Such operation programs go by a variety of names, such as "heavy soil," "extra cleaning," "solid soil," a "dirt" option, and so on. The inventors have determined that there is a need to provide alternatives to existing versions of such operation programs.
This description of the background is provided to assist with an understanding of the following explanations of exemplary embodiments, and is not an admission that any or all of this background information is necessarily prior art.

Method and apparatus for cleaning laundry


Apparatus for mapping a static magnetic field is provided. An NMR-suitable sample or array of samples is positioned in a magnetic field probe adapted to generate an alternating magnetic field and for measuring an induced signal from the sample as a result of being exposed to the alternating magnetic field. The induced signal from the sample is measured at discrete points along a helispherical or heliellipsoidal path located within the static magnetic field. Shim coils can be positioned within the static magnetic field and the current directed to the coils can be controlled as a result of the field mapping results in order to homogenize the static magnetic field. Ferromagnetic elements can be inserted in appropriate locations instead of, or in addition to, the shim coils. One such probe or any array of such probes are mounted on an actuator mechanism, which mechanism moves the probe or array of probes along a helispherical or heliellipsoidal path located within the static magnetic field. Induced signals are acquired from each probe at each of the positions along the path of the mechanism.

This invention relates to a method and apparatus for mapping magnetic fields such as in permanent or electro-magnets of resistive or superconducting design either alone or in conjunction with gradient coil assemblies associated with such magnets.
Nuclear magnetic resonance (NMR) is the resonance effect of an alternating magnetic field at right angles to a static magnetic field to change the orientation of nuclear magnetic polarization moments within a sample within the static magnetic field. The alternating magnetic field generally is applied as the magnetic component of a radio frequency field which can be applied in a continuous manner over a frequency range or which can be applied as pulses at a fixed frequency. The applied magnetic field causes an induced signal from the sample which signal is uniquely characteristic for a given nucleus and magnetic field strength. In order for the measured induced nuclear magnetism to accurately reflect the characteristic of the nuclear sample, it is essential that the static magnetic field be relatively homogeneous over the sample volume.
The use of currents in coils of varying geometry to establish magnetic field uniformly (homogeneity) is an established practice.
It is also established practise to use ferromagnetic elements inside or outside of the magnet bore in combination with shim coils or alone.
At the present time mapping of the magnetic field in a solenoidal geometry such as in NMR apparatus is conducted either by mechanical movement or NMR imaging. In mechanical movement, a single NMR probe or an array of such probes containing a sample which is small in comparison to the rate of variation of the field over the sample volume but large enough to afford sensible signal to noise, is moved mechanically through the volume of interest within the magnet. Typical trajectories of sample movement have been along the field axis of the void volume within the magnet and about circles in planes perpendicular to the field axis of the magnet. This method requires excess data in that two experiments are required which results in an excessive time to obtain the required data and is mechanically more complicated.
To date utilizing mechanical movement required manual operation and an inordinate time period to effect the mapping and also required a technician be present to record and access each reading.
A second presently utilized method is used in magnetic resonance imaging (MRI) based on pixel-by pixel observation of phase of the signal produced by a large uniform phantom. This technique has been found to be useful down to 0.1 ppm at the low fields used in imaging. However, a large frequency distribution of the signal due to field variation over the volume of interest within the magnet renders this method applicable for fine tuning only. Interpretation ambiguities and instrumental complexities also render this method unattractive for mapping highly inhomogeneous magnets.
Up to the present time, the most accurate and convenient method and apparatus for mapping a static magnetic field is disclosed in U.S. Pat. No. 4,949,044. A liquid sample is mounted on a probe adapted to generate an alternating magnetic field. The alternating magnetic field effects an individual signal from the sample. The sample is moved along a helical path at discrete locations within the static magnetic field and the induced signals at the discrete locations are recorded. As disclosed in this patent, the helical path is formed on a cylindrical surface by virtue of the apparatus disclosed to move the probe. While this method provides substantial advantages over the alternative prior art methods and is significantly simple to effect, the use of a helicylindrical path does not provide the most accurate means for defining the volume of the homogenous magnetic field. This is because the homogeneous magnetic field is most often spherical or ellipsoidal in shape, and the mathematical expression to which the map is fit during analysis involves functions (the spherical harmonics or ellipsoidal harmonics) that are properly orthogonal on the surface of the sphere and not on the surface of a cylinder.
U.S. Pat. No. 4,902,975 discloses a D.C. motor useful for moving capacitor plates in a tomography apparatus (MRI).
Routine mapping applications require several hundred separate measurements at precisely fixed positions. It would be desirable to provide a means for mapping a magnetic field which eliminates the need for a skilled technician to be present. Automatic acquisition requires a computer controlled positioning device that does not perturb the field being measured.

Apparatus for mapping static magnetic fields


A two-transistor, single capacitor ferroelectric memory cell in which a stepped voltage is applied to the drive line for writing polarization states into the capacitor. The isolation transistors are driven into cut off during the intermediate voltage level of the drive line, thereby isolating the ferroelectric capacitor plates with a balanced voltage to enhance full polarization of the ferroelectric domains, irrespective of the polarization state.

Ferroelectric crystals, including the PLZT, PZT, PLT, etc. types of material are well known as perovskites that can be polarized in one direction, or the other, and can maintain the polarization states in the absence of a voltage applied thereto. When the ferroelectric material is incorporated as a dielectric between capacitor plates, the polarization states can be stored, and remain in the polarization state without any voltage applied across the capacitor plates. When such type of capacitors are implemented in memory cells, a nonvolatile storage device is achieved. The combination of ferroelectric capacitors in a memory array allows a random access and high speed memory to be realized, where the data is stored in polarization states in a nonvolatile manner.
The use of ferroelectric material in semiconductor memories is not without various disadvantages. Ferroelectric and silicon material are not directly compatible, as the latter tends to become degraded or contaminated, unless various precautions are taken during the fabrication of the memory. U.S. Pat. No. 5,046,043 by Miller et al. discloses techniques for overcoming the problem of integrating ferroelectric material with silicon material. Another problem with ferroelectric material is that with high speed operation, such as occurs in semiconductor memories, the time period in which a voltage is actually applied across the plates of a ferroelectric capacitor is very small, often in nanoseconds, and thus the ferroelectric material does not become completely polarized during the write cycle. By this, it is meant that in high speed write cycles all or substantially all of the domains in the ferroelectric material do not become reoriented by the influence of the electric field applied across the ferroelectric material. It is a well known phenomenon that the longer the polarization voltage is applied across the ferroelectric material, the more complete the polarization of the domains in the material.
U.S. Pat. No. 4,893,272 discloses a technique for increasing the effective time period in which a polarization voltage is applied to one plate of the ferroelectric capacitor, although the actual polarizing pulse occurs in a very short period of time. The technique for writing a polarization state in the noted patent is to apply a drive pulse to the plate line of the memory cell, apply a word line signal to drive a switching transistor into a conductive state to connect the ferroelectric capacitor between the plate line and a bit line, and then remove the word line drive before removing the plate line signal to thereby isolate the voltage on the one capacitor plate. In this manner, the isolated voltage on the one capacitor plate tends to maintain a voltage across the ferroelectric material and improve retention of the polarization state, even after the plate line signal has been removed. However, the severe disadvantage of the method and structure disclosed in the noted patent is that only one polarization state is affected by the isolated voltage which is held in the capacitor plate for a longer period of time, while the other polarization state must achieve polarization during the short period of time in which the polarizing pulse is applied to the ferroelectric material, as the other plate of the capacitor is not isolated from the plate line. Thus, for all the memory cells in the patent that have been written to the one polarization state, the retention thereof is enhanced, while the other memory cells storing the other polarization state are subject to the traditional polarization retention problems. It can be appreciated that as the access speeds of memories become shorter, the polarization retention problem is exacerbated.
Another problem inherent with the polarization retention technique described in the U.S. Pat. No. 4,893,272 is that with only one plate of the ferroelectric capacitor isolated from the bit line, semiconductor substrate currents can be generated by the occurrence of switching signals on the nonisolated plate. In practice, this can present a substantial problem as the nonisolated plate of the ferroelectric capacitor is connected by a line to many other ferroelectric capacitors in the array. Hence, should zero volts be initially stored on the isolated ferroelectric capacitor plate with 5 volts applied to the nonisolated plate, and thereafter when the nonisolated plate is driven to zero volts, the isolated plate must necessarily experience a negative voltage of -5 volts. This situation can cause the generation of substrate currents which can lead to latch-up and other problems. This problem is especially serious when utilizing CMOS type of logic circuits.
From the foregoing, it can be seen that a need exists for a technique of providing symmetrical and balanced polarization states in a ferroelectric capacitor, irrespective of which state is to be stored. A further need exists for a technique of providing a high reliability memory where the polarization retention is enhanced by driving the ferroelectric capacitor with a very short pulse, and providing a voltage across both plates of the capacitor for an effectively longer period of time than the write cycle.

Symmetrical polarization enhancement in a ferroelectric memory cell


A system and method for simulating the electrical operation of a mixed analog/digital system includes the capability for analog circuit block inputs to respond to the condition in which digital gate outputs connected to the analog circuit block input are presented in high-impedance or floating signal states, thereby providing for simulation of a wide variety of mixed analog/digital designs in which this condition occurs. In a simulated design, an analog input of one or more analog circuit blocks is transformed into an analog tri-statable input-output referred to as an ioput. The ioput is capable of driving an analog signal when the digital gate outputs connected to the analog block input are presented in a high-impedance Z state; otherwise, the ioput acts as an analog input to the analog circuit block.

Simulating the electrical operating characteristics of an electrical circuit design has proven useful in the development of electrical systems and products. Design issues identified by circuit simulation can be corrected prior to the production of actual working prototypes (e.g., breadboard or integrated circuit (IC) implementations), greatly reducing redesign cycle time and costs and, thereby, leading to shortened product development cycles.
Electrical circuit simulation is typically a computation-intensive task, generally requiring the use of a computer having significant processing power and memory resources. To simulate an electrical circuit design, the design is logically constituted in computer memory from stored circuit data according to programmed instructions. Behavioral characteristics of the simulated design are the result of, among other things, the components used in the design, the arrangement of their interconnections, their operating characteristics, and their logic state specifications. A designer evaluates the operation of the electrical circuit design by observing its characteristic response in simulation. The simulated response is obtained by observing signal or waveform characteristics present at particular nodes of the circuit (e.g., test points) or at particular points in the simulation program (e.g. simulation test points or breakpoints). A simulator is said to "solve" for a particular portion of a simulated circuit, also referred to as a circuit block, by calculating the output signal characteristics produced by that circuit block in response to one or more particular input signals.
The design of electrical systems that include both analog and digital circuits or circuit blocks, known as mixed analog/digital systems, is particularly complex. A designer of this class of electrical systems is confronted not only by the design issues present for analog and digital systems individually, but is also faced with issues that arise from the inclusion of both analog and digital circuits in the same system. Mixed analog/digital system design issues are especially prevalent when the mixed design is to be implemented using a single component such as a single IC device (for example, electromagnetic coupling of high frequency switching transients from digital devices to analog circuitry).
In digital logic simulation, logic signals can take the values of 0, 1, X, and Z. The meanings of 0 and 1 comport with the standard definition of a Boolean value (i.e., a binary digit). However, a signal can also take the value "X" if the logic is such that the signal state is unknown or immaterial to the logic specification; i.e., the signal value is either 0 or 1, but the simulator cannot determine which state is present.
The value "Z," however, does not represent a state of either 0 or 1. The value "Z" is not a signal value per se; rather, "Z" represents the state of a signal not being driven or floating. When not actively driving a signal, an electronic device, such as a logic gate or other digital circuit, may present a high-impedance state, or "Z" state, at its output. This high-impedance state is useful for electrically isolating the digital circuit from the effects of other electrical signals connected to its output when that circuit or device is not driving a signal. The truth table logic specification for a digital gate frequently includes entries corresponding to values of "X" and "Z" as well as 0 and 1.
Difficulty may be experienced, however, in attempting to simulate the effect of a Z-value output on a network node and the circuit components or blocks relying upon the network node as a potential input. Because a Z-value represents high impedance or effective isolation of the digital circuit block that normally acts as a driver of the signal at the node, the node signal characteristics may remain undefined. This causes a problem for circuit components or blocks that rely upon the node as an input, and may lead to inaccurate simulation results.
Accordingly, it would be advantageous to provide a simulation system and method which is capable of handling Z-value outputs which connect to other circuit components or blocks, particularly in the context of mixed digital and analog circuit designs.

Method and system for simulation of analog/digital interfaces with analog tri-state ioputs


Reduction of noise in a device having a console with one or more microphones and a source of narrow band distributed noise located on the console is disclosed. A microphone signal containing a broad band distributed desired sound and narrow band distributed noise is divided amongst a plurality of frequency bins. For each frequency bin, it is determined whether a portion of the signal within the frequency bin belongs to a narrow band distribution characteristic of the source of narrow band noise located on the console. Any frequency bins containing portions of the signal belonging to the narrow band distribution are filtered to reduce the narrow band noise.

Many consumer electronic devices utilize a console that includes various user controls and inputs. In many applications, such as video game consoles, cable television set top boxes and digital video recorders it is desirable to incorporate a microphone into the console. To reduce cost the microphone is typically a conventional omni-directional microphone having no preferred listening direction. Unfortunately, such electronic device consoles also contain noise sources, such as cooling fans, hard-disk drives, CD-ROM drives and digital video disk (DVD) drives. A microphone located on the console would pick up noise from these sources. Since these noise sources are often located quite close to the microphone(s) they can greatly interfere with desired sound inputs, e.g., user voice commands. To address this problem techniques for filtering out noise from these sources have been implemented in these devices.
Most previous techniques have been effective in filtering out broad band distributed noise. For example, fan noise is Gaussian distributed and therefore distributed over a broad band of frequencies. Such noise can be simulated with a Gaussian and cancelled out from the input signal to the microphone on the console. Noise from a disk drive, e.g., a hard disk or DVD drive is characterized by a narrow-band frequency distribution such as a gamma-distribution or a narrow band Laplacian distribution. Unfortunately, deterministic methods that work with Gaussian noise are not suitable for removal of gamma-distributed noise. Thus, there is a need in the art, for a noise reduction technique that overcomes the above disadvantages.

Noise removal for electronic device with far field microphone on console


The luminance of a transmission mode X-ray scintillator diamond plate is dominated by induced defect centers having an excited state lifetime less than 10 msec, and in embodiments less than 1 msec, 100 usec, 10 used, 1 used, 100 nsec, or even 50 nsec, thereby providing enhanced X-ray luminance response and an X-ray flux dynamic range that is linear with X-ray flux on a log-log scale over at least three orders of magnitude. The diamond plate can be a single crystal having a dislocation density of less than 104 per square centimeter, and having surfaces that are ion milled instead of mechanically polished. The defect centers can be SiV centers induced by silicon doping during CVD diamond formation, and/or NV0 centers formed by nitrogen doping followed by applying electron beam irradiation of the diamond plate and annealing.

When operating X-ray beam apparatus, such as experimental stations of large-scale synchrotron and X-ray free electron laser (XFEL) facilities, it is important to be able to visualize and monitor the x-ray beam alignment and flux profile.
Conventional diamond X-ray beam position monitors such as a diamond fluorescent screen can be used for intermittent checking of the beam, whereby motorized stages drop the screen into place to check the beam quality and location and then remove the screen to allow the beam to pass on to the experiment. The quality of the diamond used in these screens determines not only the color of the fluorescence but also the resolution that can be achieved, because grain boundaries, non-diamond carbon, and other defects act as electron traps that produce secondary emission. Typically, such diamond fluorescent screens are an appropriate choice for larger X-ray beams, where visible detection of the fluorescence is possible. However, this approach offers limited information regarding the beam flux and profile, and does not enable "in-operando" monitoring of the beam, i.e. while an experiment is in progress or the beam is otherwise in use.
One approach that does offer in-operando monitoring is to place a diamond "blade" monitor within the beam path, where a diamond blade monitor is a diamond sheet that has been metalized with gold contacts arranged in a pattern. As the x-ray beam interacts with the diamond, a current is generated in each blade proportional to the area of interaction. By observing the current intensity among the blades, the location of the beam is determined. Diamond blade monitors are also typically applicable to larger beams where reasonable gaps between blades can be set that allow for insignificant obstruction of the beam's passage.
For smaller beam sizes, thin diamond plates with contacts applied can be used as in-operando X-ray beam monitors. The number of contacts can be varied from as few as four up to a pixelated version that supplies a digital image of the beam. A recently demonstrated, quantitative approach for transmission-mode flux density monitoring features detection of electrical charge in a lithographically patterned (pixelated) diamond plate, is described for example in T. Zhou, et al., J. Synchrotron Rad. 22,1396, (2015). This approach includes applying structured (pixelated) electrodes to diamond produced by chemical vapor deposition (CVD) to enable imaging of the X-ray beam.
Blade monitors and other diamond plates that include applied contacts have the advantage that their performance is more predictable and consistent, because the beam detection does not depend upon interactions between the X-ray beam and defects in the diamond. However, such detectors can interfere with the X-ray beam (e.g., by X-ray scattering on the pixels). Also, dedicated readout electronics are required for use with a diamond blade monitor or a pixelated detector.
X-ray transmission-mode diamond plate scintillators can be used as a noninvasive (or minimally invasive) approach to monitor the position of an X-ray beam in-operando. An X-ray transmission mode diamond scintillator is a thin plate of diamond, typically between 50 microns thick and 300 microns thick, that produces an X-ray excited optical luminescence when impacted by an X-ray beam, while absorbing only a small amount of energy from the X-ray beam. Diamond is a preferable choice for an X-ray transmission-mode scintillator due to its low X-ray absorption, high radiation hardness, and remarkable thermal and mechanical properties. Commercially available diamond plate scintillators are produced using chemical vapor deposition (CVD). They are generally polycrystalline, and luminesce primarily in "band-A" due to interactions between the X-rays and dislocation defects in the diamond. In some cases nitrogen inclusions ("N" centers) in the diamond also contribute to the luminescence of the diamond plates.
One straightforward strategy for monitoring an X-ray beam using a diamond plate scintillator is simply to observe the scintillator using a visible-light imaging apparatus. Video-monitoring of X-ray excited optical luminescence in thin diamond plate X-ray transmission mode scintillators is commonly used for the purpose of beam profile and beam position monitoring. However, the luminance of commercially available diamond scintillator plates is typically linear as a function of X-ray flux only over a dynamic range of about one order of magnitude. In addition, the X-ray luminance characteristics of commercial diamond scintillator plates can vary significantly between supposedly identical diamond plates. This is at least partly because the naturally occurring dislocation defects and N centers that give rise to the luminescence of the diamond plates can vary significantly from one diamond plate to the next i,e, between plates that are prepared using nominally identical methods.
As a result, transmission mode diamond plate scintillators generally provides only semi-quantitative information, whereby the observed profile is evaluated based on visual appearance characteristics (e.g., spatial resolution, relative brightness), typically without documented knowledge of the response linearity and dynamic detection range of the diamond plate or video monitor. For example, Park et al. (J. Y. Park, et al., J. Synchrotron Rad. 25, 869-873 (2018)) achieved 3 micron beam position stability for a monochromatic beam using a commercial diamond screen as a real-time imaging detector. However, Park did not disclose any information regarding linearity or dynamic range.
What is needed, therefore, is an apparatus and method for real-time in-operando profiling of flux density distribution in a chosen observation plane placed across the direction of propagation of an X-ray beam that can be used to derive quantitative metrics such as average beam position and intensity/photon flux over a chosen region of interest, as well as position and intensity fluctuations of the X-ray beam.

High-efficiency transmission-mode diamond scintillator for quantitative characterization of X-ray beams

Center for Technology Licensing (“CTL”) at Cornell University

Research Foundation of The City University of New York


Dynamic discovery and reporting of one or more application program topologies in a single or networked distributed computing environment allows IT professionals to maintain processes running on the network. In one embodiment, the dynamic discovery is performed by identifying one or more computers in a computer network, identifying one or more processes on each identified computer that are communicating over the network, and displaying a graphical representation of the topology of the processes communicating over the network.

Today's computer application programs are distributed in nature, relying on one or more networked computers to complete an assortment of computing tasks. One of the great challenges to information technology (IT) professionals, when measuring computer and application performance, is understanding the complex and sometimes dynamic interconnections between the various pieces of the computer application and their residence on various computing nodes.
To do this, most IT professionals rely on diagrams depicting application program interconnections. However, these diagrams are often inaccurate and out of date. The IT professionals also ask several IT individuals to piece together these connections from their recollections. However, experience has shown that these recollections are often wrong. What is needed is a way to dynamically detect and generate representations of the complex interconnections of application programs in a network environment in a programmatic way.
Conventional dynamic topology tools available in the IT workplace today fail to do this. In particular, most dynamic topology tools seek out and detect hardware interconnections such as a router that is found between computers. These types of tools target a more simplistic problem of asset management (understanding what hardware is in the network), and not of application topology (which is hardware independent).
Application topology defines how computer processes within hardware computers interact with other processes on the same and remote networked computers. An understanding of the application topology allows proper maintenance of pieces of the application programs in the network. For example, if an application is running slowly, the application topology is used to identify all pieces of the application that reside on the various remote computers, so that those application pieces can be examined. However, conventional tools are unable to display the application topology. Instead, they identify hardware components in the distributed computing environment, without identifying application processes that are being executed by the hardware components.

International Business Machines Corporation


The magnetic resonance signal analyzer allows to generate a large variety of test signals including one or more frequencies. The test signals can be applied as electromagnetic fields or as currents to material under test. An electromagnetic or electrical response signal of the material under test be applied to the analyzer for processing to determine the response pattern of the material under test.

The apparatus of the present invention relates to magnetic resonance test instrumentation. It exposes material to be tested to an electro-magnetic field of selected frequencies and analyzes the magnetic resonance responses of the material. The magnetic resonance analyzer offers new advantages in the field of material analysis. It has been shown that the applicability of such an analyzer exceeds the range of tissue analysis and other medical applications. The magnetic resonance analyzer measures the degree and type of response of a matter under test, and by comparison with reference matter it assists in recognizing deviations from the desired response. This capability is enhanced by testing with a test pattern which relates to the significant characteristics for the particular matter under test.

Computerized magnetic resonance analyzer


A system, method, and computer program are provided for providing a vulnerability assessment of a network of industrial automation devices. A user interface that enables a user to select an IP address range and a plurality of industrial automation protocols is provided. The system attempts to establish a communication session with each device within the selected IP address range using each of the selected industrial automation protocols. If a communication session is established with a device, the system attempts to read device information. If device information can be read, the system determines a threat level associated with the device using the device information. The system then provides a vulnerability assessment to the user, identifying each device with which a communication session was established and the industrial automation protocol(s) with which the communication session was established and any threat level determined for the device.

1. Field of the Invention
This invention relates generally to a vulnerability assessment system and, more particularly, to a system and method for providing a vulnerability assessment of a network of industrial automation devices.
2. Description of the Background Art
Industrial automation devices, such as diesel generators, fuel cells, lighting systems, chillers, pumps, boilers, manufacturing equipment, automatic transfer switches, etc., may be connected together on a network so that they can be centrally monitored and managed. For example, a hospital may need to monitor its power supply and energy consumption to ensure that it has adequate power for all the equipment in the hospital. Similarly, an industrial manufacturing facility may network its equipment so that it can monitor its power supply and consumption to ensure that energy is used efficiently.
While being able to centrally monitor and manage such devices is becoming increasingly necessary for energy management and other purposes, the problem with connecting such devices to a network is that they become vulnerable to attack. If a device can be remotely accessed, the device can also be remotely controlled. For example, another party with a harmful intent would be able to disrupt power to a hospital, airport, or other critical facility.
Therefore, there is a need to be able to assess the vulnerability of networked industrial automation devices. There are known network intrusion detection tools that detect vulnerabilities using the TCP/IP protocol. These tools are used to detect vulnerabilities of office and personal computing devices such as laptops, desktops, printers, servers, etc.
However, industrial automation devices may run firmware or other software that communicates via one or more industrial automation protocols such as Modbus, BACnet, OPC, etc. A network of industrial automation devices may use a number of different industrial automation protocols. A TCP/IP port associated with one protocol may be secure while a TCP/IP port associated with another protocol may not be secure. Therefore, there is a need for a tool that can assess the vulnerability of a network of industrial automation devices with respect to several different industrial automation protocols.

System, method, and computer program for providing a vulnerability assessment of a network of industrial automation devices