A method of generating a code sequence and method of adding additional information using the same are disclosed, by which a code sequence usable for a channel for synchronization is generated and by which a synchronization channel is established using the generated sequence. The present invention, in which the additional information is added to a cell common sequence for time synchronization and frequency synchronization, includes the steps of generating the sequence repeated in time domain as many as a specific count, masking the sequence using a code corresponding to the additional information to be added, and transmitting a signal including the masked sequence to a receiving end.

First of all, a synchronization channel (hereinafter abbreviated SCH) as an example of a specific channel is explained as follows.
In order for a user equipment to communicate with a base station in a mobile communication system, the user equipment primarily performs synchronization with the base station on SCH and then secondarily performs a cell search. A series of process for performing synchronization with a base station and obtaining an ID of a cell to which a user equipment belongs is called a cell search.
Generally, a cell search is classified into an initial cell search executed in case of a user equipment's 'power on' in an initial mode and a neighbor cell search performed by a user equipment in a connection mode (i.e., normal mode) or idle mode to search a neighbor base station.
FIG. 1 is a flowchart of a cell search procedure.
If the 3GPP LTE system is taken as an example among various communication systems, the SCH structure for the cell search is classified into a hierarchical structure and a non-hierarchical structure according to a time symbol synchronization and cell search method.
And, a cell ID obtaining method is classified into a first method of searching cell groups and searching reference signals for a final cell ID and a second method of obtaining a cell ID from SCH only.
In case of the first method, a cell group ID is obtained from SCH. In case of the second method, a final cell ID (i.e., cell ID) is obtained from SCH.
SCH following the hierarchical structure is explained as follows.
First of all, the SCH following the hierarchical structure is classified into a primary SCH (hereinafter abbreviated P-SCH) and a secondary SCH (S-SCH) like SCH of WCDMA.
The P-SCH is a channel on which all cells or sectors use the same signal and performs initial symbol synchronization and frequency synchronization. A signal value of P-SCH is already known by all user equipments. So, initial time symbol synchronization can be executed by performing cross-correlation between a received signal and a predetermined signal. Such a series of procedures are called cross-correlation based detection.
After time, symbol and frequency synchronizations have been obtained, cell ID or cell group ID detection is performed at a position of S-SCH previously indicated by timing synchronization information obtained from P-SCH.
Meanwhile, a method of multiplexing P-SCH and S-SCH can be classified into TDM, FDM and CDM.
FIG. 2 is a structural block diagram of SCH following a hierarchical structure.
An example shown in FIG. 2 corresponds to an example of multiplexing by TDM. Positions of P-SCH and S-SCH and a count of OFDM symbols including P-SCH and S-SCH may differ from the case shown in FIG. 2.
Referring to FIG. 2, SCH is generated via two OFDM symbols. A radio frame includes 20 sub frames, and a specific radio frame is selected to transmit SCH only.
In the example shown in FIG. 2, first and second OFDM symbol provide SCH. Yet, an OFDM symbol which provides SCH can be another OFDM symbol, e.g., a last OFDM symbol.
SCH following the non-hierarchical structure is explained as follows.
First of all, a non-hierarchical SCH is characterized in having a repetitive waveform within an OFDM symbol in time domain. This enables a user equipment to perform a blind detection of initial time symbol synchronization through auto-correlation of a received signal using the repetitive characteristic of signal. And, this detection is called auto-correlation based detection.
After completion of the time and frequency synchronizations, cell ID detection or cell group ID detection are carried out at a position of the detected SCH.
FIG. 3 is a structural block diagram of SCH following a non-hierarchical structure. An OFDM symbol or subframe to form SCH can be freely changed.
In the above-explained hierarchical structure, cross-correlation based detection can be carried out based on Formula 1.
                                                                                d                ^                            =                                                                    arg                                                                                max                                    d                                                                  {                                                            R                                                                    (                        d                        )                                                              |                                          0                      ≤                      d                      ≤                                                                        N                          f                                                -                        1                                                                              }                                                                                R                                                  (                  d                  )                                            =                                                ∑                                      p                    =                    1                                    P                                                                                ∑                                          q                      =                      1                                        Q                                                                          (                                                                  (                                                                              ∑                                                          m                              =                              1                                                        M                                                                                                                                                                ∑                                                                      n                                    =                                                                                (                                                                                m                                          -                                          1                                                                                )                                                                                L                                                                                mL                                    -                                    1                                                                                S                                      *                                                                                (                                      n                                      )                                                                                r                                                                              p                                        ,                                        q                                                                                (                                                                              n                                        +                                        d                                                                            )                                                                                                                                        2                                                                          )                                            /                                              (                                                                              ∑                                                          n                              =                              0                                                                                N                              -                              1                                                                                                                                                                r                                                                      p                                    ,                                    q                                                                                (                                                                      n                                    +                                    d                                                                    )                                                                                                                                        2                                                                          )                                                              )                                                                                (                          N              =              ML                        )                                                                                [                  Formula                                                              1                ]
In Formula 1, 'R(d)' is a cost function to find a start point for synchronization acquisition, '{circumflex over (d)}' is a value to maximize the R(d), and 'Nf' is a length of a radio frame. 'P' indicates a count of symbols used for averaging. 'Q' indicates a count of receiving antennas of a user equipment. 'L' indicates a count of Parts for M-partial correlation. 'N' indicates a point of FFT/DFT operation. 'rp,q(n)' indicates a signal received by a qth receiving antenna in a pth P-SCH symbol. And, 'S(n)' indicates a known sequence inserted in P-SCH. In this case, in the environment where frequency offset exists, if symbol synchronization via cross-correlation based detection is simply carried out, performance is degraded. So, M-partial correlation can be applied. [Y.-P. E. Wang and T. Ottosson, "Cell search in W-CDMA", Selected Areas in Communications, IEEE Journal on, vol. 18, pp. 1470-1482, August 2000.]
In the hierarchical structure shown in FIG. 2, a method of estimating frequency offset can be represented as Formula 2.
                              Δ                                                              f                =                                            f              s                                      π                                                                                N                                          arg                                {                          -                                                ∑                                      p                    =                    1                                    P                                                                                ∑                                          q                      =                      1                                        Q                                                                                [                                                                              ∑                                                          n                              =                              0                                                                                N                                /                                2                                                            -                              1                                                                                (                                                                                S                                  *                                                                                (                                  n                                  )                                                                                r                                                                      p                                    ,                                    q                                                                                (                                                                      n                                    +                                                                          d                                      ^                                                                                )                                                                                )                                                                          ]                                            *                                                                                [                                                                              ∑                                                          n                              =                                                              N                                /                                2                                                                                N                              -                              1                                                                                (                                                                                S                                  *                                                                                (                                  n                                  )                                                                                r                                                                      p                                    ,                                    q                                                                                (                                                                      n                                    +                                                                          d                                      ^                                                                                )                                                                                )                                                                          ]                                            }                                                                                [                  Formula                                                              2                ]
In Formula 2, 'fs' means a sampling frequency and 'arg{ }' means a phase component for a complex number. And, the frequency offset is generated from the difference between frequencies generated by oscillators provided to a base station and a user equipment, respectively.
And, the auto-correlation based detection used for the non-hierarchical structure shown in FIG. 3 is represented as Formula 3.
                              R                                (            d            )                          =                              ∑                          p              =              1                        P                                                        ∑                              q                =                1                            Q                                                  (                                                                                                                                      ∑                                                  n                          =                          0                                                                                N                            /                            2                                                    -                          1                                                                                r                                                          p                              ,                              q                                                        *                                                                                (                                                          n                              +                              d                                                        )                                                                                r                                                          p                              ,                              q                                                                                (                                                          n                              +                              d                              +                                                              N                                /                                2                                                                                )                                                                                                                    2                                /                                                      ∑                                          n                      =                      0                                                                                N                        /                        2                                            -                      1                                                                                (                                                                                                                                                                r                                                              p                                ,                                q                                                                                (                                                              n                                +                                d                                                            )                                                                                                                                2                                            +                                                                                                                                                        r                                                              p                                ,                                q                                                                                (                                                              n                                +                                d                                +                                                                  N                                  /                                  2                                                                                )                                                                                                                                2                                                              )                                                              )                                                          [                  Formula                                                              3                ]
And, the frequency offset can be estimated in the non-hierarchical structure in a following meaner of Formula 4.
                              Δ                                                              f                =                                            f              s                                      π                                                                                N                                          arg                                {                          -                                                ∑                                      p                    =                    1                                    P                                                                                ∑                                          q                      =                      1                                        Q                                                                                ∑                                              n                        =                        0                                                                    N                                                  2                          -                          1                                                                                [                                                                                r                                                              p                                ,                                q                                                                                (                                                              n                                +                                                                  d                                  ^                                                                                )                                                                                ]                                                *                                                                                [                                                                              r                                                          p                              ,                              q                                                                                (                                                          n                              +                                                              d                                ^                                                            +                                                              N                                2                                                                                )                                                                          ]                                                                                }                                              [                  Formula                                                              4                ]
The cell search method uses the same method for both of the hierarchical structure and the non-hierarchical structure.
Comparison between the hierarchical SCH and the non-hierarchical SCH is explained as follows.
First of all, communication systems are classified into a synchronous network and an asynchronous network. In particular, the synchronous network is a network having the same transmission start time for all sectors. Yet, in the asynchronous network, although sectors within one Node-B have the same transmission start time, a transmission start time is random between Node-Bs.
In case that both of the synchronous network and the asynchronous network need to be supported, the hierarchical SCH is preferably used.
FIG. 4 is a diagram of performance comparison between hierarchical SCH and non-hierarchical SCH in a synchronous system. And, FIG. 5 is a diagram of performance comparison between hierarchical SCH and non-hierarchical SCH in an asynchronous system.
Referring to FIG. 4 and FIG. 5, a case of using a hierarchical structure improves performance of cell search. Yet, in the hierarchical structure, cross-correlation detection should be used for timing synchronization acquisition and frequency offset estimation performance of the hierarchical structure is inferior to that of a non-hierarchical structure. FIG. 6 is a diagram of residual frequency offset error in a synchronous system, and FIG. 7 is a diagram of residual frequency offset error in an asynchronous system.
In brief, each of the hierarchical SCH and the non-hierarchical SCH has its own problems.
To solve these problems, the hybrid SCH scheme has been proposed. In the hybrid SCH scheme the hierarchical SCH and the non-hierarchical SCH are combined together.
FIG. 8 is a diagram to explain a hybrid SCH scheme.
Referring to FIG. 8, a hybrid SCH includes P-SCH and S-SCH like the hierarchical SCH. Yet, P-SCH is assigned to a frequency index with a specific interval in a specific OFDM symbol. In other words, a sequence included in P-SCH is configured in a manner that a specific waveform is repeated in time domain by a prescribed count.
Meanwhile, S-SCH is configured in a same manner of the hierarchical SCH.
In case of the hybrid SCH, P-SCH is configured by a cell common sequence. Yet, by allocating the respective sequences (P0, P1, P2, . . . , PN-2, PN-1) corresponding to P-SCH to a frequency domain with a specific interval, cell search and frequency offset characteristics are enhanced.
Formula 5A shows a method of estimating a synchronization in a hybrid SCH and Formula 5B shows a method of estimating a frequency offset.
                                                                                d                  ^                                =                                                      arg                    d                                                                                max                                                        {                                                                  R                                                                          (                          d                          )                                                                    |                                              0                        ≤                        d                        ≤                                                                              N                            f                                                    -                          1                                                                                }                                                                                R                                                  (                  d                  )                                                      =                                                            (                                                            ∑                                              m                        =                        0                                                                    M                        -                        1                                                                                                                                                              ∑                                                          m                              =                              mL                                                                                (                                                                      m                                    +                                    1                                                                    )                                                                                L                                                            -                              1                                                                                p                                *                                                                                (                                n                                )                                                                                r                                                                                (                                                                  d                                  +                                  n                                                                )                                                                                                                            2                                                        )                                /                                  (                                                            ∑                                              n                        =                        0                                                                                N                            fft                                                    /                          2                                                -                        1                                                                                                                                  r                                                                                (                                                          d                              +                              n                                                        )                                                                                                                      2                                                        )                                            +                                                (                                                            ∑                                              m                        =                        0                                                                    M                        -                        1                                                                                                                                                              ∑                                                          n                              =                              mL                                                                                (                                                                      m                                    +                                    1                                                                    )                                                                                L                                                            -                              1                                                                                p                                *                                                                                (                                                                                N                                      fft                                                                        2                                                                    +                                  n                                                                )                                                                                r                                                                                (                                                                                N                                      fft                                                                        2                                                                    +                                  d                                  +                                  n                                                                )                                                                                                                            2                                                        )                                /                                  (                                                            ∑                                              n                        =                        0                                                                                N                            fft                                                    /                          2                                                -                        1                                                                                                                                  r                                                                                (                                                                                N                                  fft                                                                2                                                            +                              d                              +                              n                                                        )                                                                                                                      2                                                        )                                                                                (                                                            N                  fft                                /                2                            =              ML                        )                                              [                  Formula                                                              5                    A                ]                                          f          ^                =                                            N              fft                                      2                            π                                                                                N                  fft                                /                                  N                  rep                                                                        arg                                {                                          ∑                                  n                  =                  0                                                                                N                      fft                                        /                    2                                    -                  1                                                                                [                                          r                                                                    (                                                                              d                            ^                                                    +                          n                                                )                                                              ]                                    *                                                                  [                                      r                                                              (                                                                        d                          ^                                                +                        n                        +                                                                              N                            fft                                                    /                          2                                                                    )                                                        ]                                                      }                                              [                  Formula                                                              5                    B                ]

Method of generating code sequence and method of transmitting signal using the same


This invention provides a method for the treatment or amelioration of the symptoms of venomous bites or stings which comprises administering to a mammal in need thereof one or more 5-HT.sub.2 antagonists.

Venomous bites and stings can cause a variety of reactions depending upon the source of the venom and the sensitivity of the individual or animal. In some cases, venom from a bite or sting can cause anaphylaxis, an immediate hypersensitivity which can be life-threatening. In other cases, certain venoms can cause cutaneous "local" reactions. Cutaneous local reactions can be characterized as 1) "non-allergic" reactions which are of limited size and duration or as 2) "allergic" or "large" local reactions which are typically larger in size and longer in duration. With regard to Hymenoptera venoms (bee, wasp, hornet and yellowjacket), "the non-allergic local reaction is a toxic response to venom constituents, while the large local reaction appears to be caused by an allergic reaction to venom proteins." See, D. N. Wright, Local Reactions To Stinging Insects (Hymenoptera), Allergy Proc. 11(1):23-28 Jan.-Feb. 1990).
Upon receiving a venomous bite or sting, a variety of symptoms can be exhibited due to the venom, including pruritus, erythema, urticaria, angioedema, soft tissue swelling, inflammation of the affected area and pain in the affected area.
When injected subcutaneously, many venoms from bites and stings induce extravasation from adjacent blood vessels. See, V. Cattell, Focal Mesangial Proliferative Glomerulonephritis In The Rat Caused By Habu Snake Venom: The Role Of Platelets, British J. of Exp. Pathol., 60(2):201-208 (April 1979); In addition, the venoms induce platelet aggregation and mast cell degranulation, two components of inflammation along with extravasation. Serotonin release has also been associated with the injection of venoms. See, for instance, Y. Ozaki, et al, Mastoparan, A Wasp Venom, Activates Platelets Via Pertussis Toxin-Sensitive GTP-Binding Proteins, Biochem. Biophys. Res. Commun., 170(2):779-85 (Jul. 31, 1990) and C. Wang, et al, Experimental Study of Chinese Agkistrodon Actus Venom In Activation Of Rabbit Platelets In Vivo, Hua Hsi I Ko Ta Hsueh Hsueh Pao, 25(1):38-40 (March 1994).
Since the discovery of serotonin (5-hydroxytryptamine, 5-HT) over four decades ago, the cumulative results of many diverse studies have indicated that serotonin plays a significant role in the functioning of the mammalian body, both in the central nervous system and in peripheral systems as well. Morphological studies of the central nervous system have shown that serotonergic neurons, which originate in the brain stem, form a very diffuse system that projects to most areas of the brain and spinal cord. R. A. O'Brien, Serotonin in Mental Abnormalities, 1:41 (1978); H. W. M. Steinbusch, Handbook of Chemical Neuroanatomy, Volume 3, Part II, 68 (1984); N. E. Anden, et al., Acta Physiological Scandinavia, 67:313 (1966). These studies have been complemented by biochemical evidence that indicates large concentrations of 5-HT exist in the brain and spinal cord. H. W. M. Steinbusch, supra.
With such a diffuse system, it is not surprising that 5-HT has been implicated as being involved in the expression of a number of behaviors, physiological responses, and diseases which originate in the central nervous system. These include such diverse areas as sleeping, eating, perceiving pain, controlling body temperature, controlling blood pressure, depression, schizophrenia, and other bodily states. R. W. Fuller, Biology of Serotonergic Transmission, 221 (1982); D. J. Boullin, Serotonin in Mental Abnormalities 1:316 (1978); J. Barchas, et al., Serotonin and Behavior, (1973).
Serotonin plays an important role in peripheral systems as well. For example, approximately 90% of the body's serotonin is synthesized in the gastrointestinal system, and serotonin has been found to mediate a variety of contractile, secretory, and electrophysiologic effects in this system. Serotonin may be taken up by the platelets and, upon platelet aggregation, be released such that the cardiovascular system provides another example of a peripheral network that can release and respond to serotonin. Given the broad distribution of serotonin within the body, it is understandable that tremendous interest in drugs that affect serotonergic systems exists. In particular, receptor-specific agonists and antagonists are of interest for the treatment of a wide range of disorders, including anxiety, depression, hypertension, migraine, compulsive disorders, schizophhrenia, autism, neurodegenerative disorders, such as Alzheimer's disease, Parkinsonism, and Huntington's chorea, and cancer chemotherapy-induced vomiting. M. D. Gershon, et al., The Peripheral Actions of 5-HYDROXYTRYPTAMINE, 246 (1989); P. R. Saxena, et al., Journal of Cardiovascular Pharmacology, 15:Supplement 7 (1990).
Serotonin produces its effects on cellular physiology by binding to specialized receptors on the cell surface. Multiple types of receptors exist for many neurotransmitters and hormones, including serotonin. The existence of multiple, structurally distinct serotonin receptors has provided the possibility that subtype-selective pharmacologic agents can be produced. The development of such compounds could result in new and increasingly selective therapeutic agents with fewer side effects, since activation of individual receptor subtypes may function to affect specific actions of the different parts of the central and/or peripheral serotonergic systems.
An example of such specificity can be demonstrated by using the vascular system as an example. In certain blood vessels, stimulation of certain 5-HT receptors on the endothelial cells produces vasodilation while stimulation of certain 5-HT receptors on the smooth muscle cells produces vasoconstriction.
Currently, the major classes of serotonin receptors (5-HT.sub.1, 5-HT.sub.2, 5-HT.sub.3, 5-HT.sub.4, 5-HT.sub.5, 5-HT.sub.6, and 5-HT.sub.7) contain some fourteen to eighteen separate receptors that have been formally classified based on their pharmacological or structural differences. For an excellent review of the pharmacological effects and clinical implications of the various 5-HT receptor types, see Glennon, et al., Neuroscience and Behavioral Reviews, 14:35 (1990).! discoveries.
One class of serotonin receptors is the 5-HT.sub.2. Of this class, several subtypes are known to exist. These subtypes include 5-HT.sub.2A, 5-HT.sub.2B and 5-HT.sub.2C. The subtype 5-HT.sub.2A is located in many tissues, including but not limited to, the vascular smooth muscle, platelets, lung, CNS and gastrointestinal tract. This receptor is thought to be associated with several effects: for example, vasoconstriction, platelet aggregation, and bronchoconstriction. The 5-HT.sub.2B receptor is localized in the rat lung, stomach fundus, uterus, bladder, and colon. Interesting areas of 5-HT.sub.2B receptor localization in the human include, but are not limited, to the brain and blood vessels. Subtype 5-HT.sub.2C is located in the CNS with a high density in the choroid plexus.
Because of the widespread dissatisfaction with the current treatments for venomous bites and stings within the affected population, there exists a need for a more efficacious and safe treatment. The present invention provides such a treatment.

Methods of treating or ameliorating the symptoms of venomous bites and stings


An apparatus for skinning fish fillets having the roller-presser shoe-structure comprises an oscillating knife (17) is particularly appropriate for skinning fillets of flatfish, i.e. fillets of fish which show a rather intimate and close connection between the skin and the muscle meat at least partially caused by fine tendons. In order to improve the insufficient yield in fillet meat caused by the structure of such machines, and in order to obtain a remaining of the so-called silver mirror on the fillet meat, the presser shoe (6) carrying and guiding the oscillating knife (17) is arranged to pivot about the axis (9) of the roller (3) against spring force, and the pivoting movement is used for retracting the oscillating knife (17), so that the cutting edge (19) thereof comes to lie behind a stationary cutting edge (13) formed on the presser shoe (6) at the entrance side thereof. Thereby, a change of the type of skinning cut occurs during the skinning after the initiating cutting by the oscillating knife (17) by the presser shoe (6) being entrained due to the entrance of the skin into the gap (8) between the presser shoe (6) and the roller (3).

1. Field of the Invention
The invention relates to an apparatus for skinning fish fillets, comprising a skin entraining roller driven to rotate, a presser shoe having a presser face opposing the circumferential surface of the skin entraining roller and leaving a gap with respect to the roller, and a skinning knife driven to oscillate, which, with its cutting edge opposes the circumferential surface of the skin entraining roller at a distance thereto.
2. Prior Art
Such skinning apparatus is e.g. known from German Patent 37 00 324. In this known apparatus, the skinning knife is guided in a slot of the presser shoe, the position of the cutting edge being defined, relative to the blunt edge of the pressure shoe, by guiding elements in the shape of feather keys, said blunt edge confining the entrance side of the presser face. The guiding elements engage corresponding recesses in the skinning knife and ensure that the cutting edge lies slightly upstream or ahead of said pressure shoe edge.
This apparatus, which has been especially designed for the skinning of fillets of flatfish, has brought about excellent results and proved extremely reliable, because the rather intimate and strong connection of the skin with the muscle flesh which is characteristic for this species of fish and is caused by fine tendons, can be severed without problems.
However, with regard to the yield in fillet meat to be obtained with this apparatus, certain disadvantages occur in the application of this design. Such drawbacks already become apparent optically in that the so-called "silver mirror", which is a quality characteristic of skinned fillets, is missing on the skin side of the fillets. The reason for this is that this skinning procedure depends on the severing of a layer of uniform thickness including the skin, which thickness can be predetermined by setting or adjustment. By such processing it cannot be avoided that, in regions in which the skin is thinner than in other regions, a layer of meat and thus the silver mirror are severed as well.
Although it is known that the silver mirror can be maintained in the case of fillets of flatfish when using a fixedly arranged knife having a defined sharpness, no constant and reliable operation can be carried out therewith. Finally, there is a further drawback in that the tail area splits along the line of the backbone so that the skinned fillet assumes a dovetail-shaped appearance which is considered to be a quality impairment.
3. Object of the Invention
It is the main object of the present invention to remove the drawbacks of the prior art apparatus.
It is a particular object to suggest an apparatus by means of which it becomes possible to skin flatfish fillets while maintaining their silver mirror.
It is yet another important object of the invention to suggest an apparatus which safeguards that a splitting of the tail area is avoided.

Nordischer Maschinenbau Rud.Baader GmbH + Co KG


Systems and methods are provided for monitoring and logging all activity occurring in a system. The logged activity may include keystroke entries input into the system, user and/or application interactions with the system, access restriction conflicts, and the like. The logged activity may be stored in at least two datastores, at least one of which is an immutable, append-only datastore. Storage of the logged activity in the immutable, append-only datastore is performed using hash algorithms. Attempts at manipulating or at hiding malicious or unauthorized activity can be recognized due to all activity being captured in the immutable, append-only datastore.

Deployments such as platforms for analyzing data can be subject to malicious attacks. Malicious attacks can entail the access and/or analysis of data that an attacker does not have the authority/permission to access, analyze, or otherwise manipulate. Malicious attacks can also be attempts by an attacker to hide their tracks by deleting evidence of their unauthorized activity. For example, a user may attempt to delete activity logs evidencing the user's malicious activity in a system. The user may perform these actions directly or through a compromised system agent or administrator.

Systems and methods for tamper-resistant activity logging


A system and method for regenerating secret keys that have been used to encrypt communications between two parties are disclosed. The system and method involve securely escrowing only one of the private values that the parties use in a Diffie-Hellman exchange to establish secure communications between the parties. The public value for each communication session is controlled after the escrow of the private value, and the secret keys are regenerated from the escrowed private value and the controlled public values. The escrowed private value is transmitted to the escrow center with full proof of security and authenticity, and the escrowed private value can be changed and re-sent to the escrow center.

This invention relates generally to cryptography and more particularly to a system and method for regenerating secret keys involved in Diffie-Hellman exchanges. Upon regeneration of secret keys, messages in secret communications are decrypted and observed.
Cryptography involves the encoding and decoding of messages, and has utility in the field of secure communications where issues of privacy and authentication of messages in public communications are important concerns. A privacy system prevents the extraction by unauthorized parties (xe2x80x9ceavesdroppersxe2x80x9d) of information from messages transmitted over a communication channel, thus assuring that only the intended recipient is able to read the message. An authentication system ensures detection of any modification of the message by unauthorized parties (xe2x80x9cintermeddlersxe2x80x9d), thus assuring the receiving party that the message is exactly what was sent by its sender. An authentication system also assures the recipient that the true sender actually sent the message. Depending upon safeguards, any communication channel may be threatened with eavesdropping or intermeddling, which thereby threatens the integrity of the messages or the identities of the transmitters.
FIG. 1 illustrates the flow of information in a conventional cryptographic communication. There are three parties: a transmitter 102, a receiver 104, and eavesdropper or intermeddlers 106. The transmitter 102 generates a message 108 to be communicated over a communication media 114 to the receiver 104. In order to prevent the eavesdropper or intermeddlers 106 from reading the messages, transmitter 102 encrypts the message 108 using an encryption key 110 producing encrypted message 112, which is sent to the receiver 104 over communications media 114. The legitimate receiver 104 must know how to decrypt the encrypted message 112 using decrypting key 116 to have access to the original message 108. The roles of transmitter 102 and receiver 104 are reversible, that is, a receiver 104 becomes a transmitter 102, which transmits encrypted messages 112 to the former transmitter 102, which in turn becomes receiver 104.
Encrypted messages in communication systems solve message security problems when message encryption techniques are properly used in the hands of legitimate personnel. However, in the hands of criminals or terrorists or other malicious parties, encrypted communications are an aid to illegal activities because the messages in the communications are secret to the public. The United States Government, motivated by a desire to prevent illegitimate activities, has required that it have access to encrypted communications so that it can observe the original, unencrypted messages 108. The government therefore has proposed various plans that require the parties involved in encrypted communications to hold in trust, or xe2x80x9cescrow,xe2x80x9d the encryption keys 110 used to encrypt messages 108 for some period of time. These encryption keys 110 must be readily surrendered to the government upon request. Having acquired the encryption keys 110, the government then has access to the original message 108 through decryption of the encrypted message 112 which are exchanged between suspect parties.
The requirement to hold encryption keys for a long period of time has great impact on embedded communications devices, especially network routers, as most routers do not have any hard disk or other memory devices to store encryption keys.
Additionally, it is desirable to implement a cryptographic scheme utilizing ephemeral keys which are derived from a Diffie-Hellman exchange, with one key per communication session. These ephemeral keys are then destroyed after each session. Federal law mandates access to keys for a period of up to seven years, requiring storage of hundreds of thousands of keys since hundreds of thousands of communication sessions may occur in a period of seven years with each session generating a unique key.
Moreover, it is desirable to embrace a standard where any key escrow scheme does not preclude interoperability with existing standards. For example, if one party implements a key escrow scheme and others do not implement that key escrow scheme, it is desirable that the party with the escrow scheme is not precluded from inter-operating with the others.
It is further desirable that a key escrow scheme can be seamlessly added to any standard-compliant key management protocol which utilizes a Diffie-Hellman exchange in order to additionally generate ephemeral secret keys such that the additional implementation which performs escrow remains fully standard-compliant. The escrow requirement thus raises the concern that the escrow of keys must be done securely, i.e., with full proof of security and authentication of a party that is depositing a key in escrow.
Attempts at escrowing ephemeral keys have been discussed by Silvio Micali, xe2x80x9cGuaranteed-Partial Key Escrow,xe2x80x9d MIT/LCS/TM-537, Laboratory for Computer Science, Massachusetts Institute of Technology, Cambridge, Mass. (1995); and by Mihir Bellare and Shafi Goldwasser, xe2x80x9cVerifiable Partial Key Escrow,xe2x80x9d University of California, San Diego, CSE Department Technical Report. Both of these papers describe key escrow schemes that take advantage of a Diffie-Hellman exchange and allow for recovery of communications using a partially escrowed key. Each key used for bulk encryption by a router, for example, is partially escrowed. However, each of these schemes concerns only the partial escrow of a single ephemeral key, and does not deal with the problem of ephemeral session keys, where hundreds or thousands of keys are generated during a period of time of up to seven years.
A key escrow scheme applicable to network communications devices is discussed in xe2x80x9cEscrowed Encryption Standard (ESS),xe2x80x9d National Institute for Standards and Technology, Federal Information Processing Standards Publication (FIPS PUB) 185, 1994. However, this approach involves a hardware solution, and requires both parties in a communication to be active participants in the escrow operation.
Another key escrow scheme, also applicable to network communications devices, is disclosed by Jim Omura, xe2x80x9cAlternatives to RSA Using Diffie-Hellman with DSS,xe2x80x9d White Paper, Cylink, September 1995. In this scheme, the escrowing party sends the key to an escrow agent, and the agent in return provides the escrowing party a public number to use in the next Diffie-Hellman exchange. However, this scheme involves the escrow of a single key and requires interaction with the escrow agent for each key.
In light of the above shortcomings of prior art techniques in encryption key escrowing, there is a need for an implementation that allows a complete recovery of all encryption keys involved in Diffie-Hellman exchanges and yet still prevents eavesdroppers and intermeddlers from capturing the secrets of private communications. In accordance with an embodiment, there are no special headers or messages required between parties for secure communications. Neither is there a special hardware requirement for any party involved in the communications.
There is also a need to provide a key-escrowing scheme that requires only a single interaction with the escrow agent during a time period of variable length and eliminates the needs to escrow each and every key, and where there is no necessity to store all of the session keys while preserving the ephemeral nature of these keys.
There is also a need to remove the requirement that a participating networking communication device maintain session keys after the life of the session has passed, and thereby to retain the ephemeral nature of the keys.
There is also a need to allow a party to take part in an escrow and to continue inter-operating with existing standards and methods of secured communications.
There is also a need to allow a solution that is applicable to all devices on a network, including hosts, servers and routers.
There is also a need to allow third party law enforcement officers to recover communication information and to monitor messages exchanged between the parties taking part in the Diffie-Hellman communications.
There is also a need to allow recovery of the communication even if only one party was involved in the escrowing scheme.
There is also a need to maintain the security strength of the Diffie-Hellman exchange.
There is also a need to escrow the key to the escrowing center with confidentiality and proof of ownership, thereby assuring both privacy and authenticity of the escrowed information.
The foregoing needs, and other needs that will become apparent from the following description and the appended claims, are fulfilled by the present invention, which comprises, in one aspect, a method of regenerating ephemeral secret keys for Diffie-Hellman communication sessions. A key regeneration method enables a third party xe2x80x9cLxe2x80x9d (such as a law enforcement officer) to gain access to communications previously exchanged between a party xe2x80x9cAxe2x80x9d and any other parties e.g. xe2x80x9cBxe2x80x9d or xe2x80x9cC.xe2x80x9d Party A initially makes a private value Xa available to the third party L and, in one embodiment, party A escrows Xa to an escrow center, where the private value Xa is kept secret and made available only to third party L. Party A may then engage in any number of Diffie-Hellman exchanges with any remote parties in a plurality of communication sessions for a time period t.
For the first communication session between party A and another party B after the escrowing of private value Xa to the escrow center and prior to the conclusion of the period t, party A generates public value Ya from the equation:
Ya=g(Xa+n)modp,
where n equals a value such as 0, while party B generates public value Yb from the equation:
Yb=gXbmodp
The parties A and B provide their respective public values Ya and Yb to the other party, i.e., Ya to party B and Yb to party A. Both parties A and B then generate, respectively, a secret key Kab and Kba for their secret communication session, where:                               K                                xe2x80x83                              a                                xe2x80x83                              b                =                  Y                                xe2x80x83                                          b                          X                                            xe2x80x83                                          a                                                      xe2x80x83                              mod                                xe2x80x83                              p                                                  =                                    K                                            xe2x80x83                                          b                                            xe2x80x83                                          a                                                  xe2x80x83                        =                          xe2x80x83                                                                  Y                                                  xe2x80x83                                                                  a                                      X                                                              xe2x80x83                                                            b                                                                                xe2x80x83                                                mod                                                  xe2x80x83                                                p                            =              K                                      ,
such that K is a common secret key for both parties. For each of the successive communication sessions, whether to party B or to any other party C, for example, party A generates public value Ya from the same equation Ya=g(Xa+n)mod p, where n is a new value. The new value n may be created, for example, by increasing a previous value of n by 1. Party C generates public value Yc from the equation Yc=gXcmod p, where Xc is a random value of sufficient entropy to guarantee the strength of the secret value K.
When the third party L desires to gain access to communications between the party A and any other party B or C, third party L needs to regenerate the secret key Kab involved in the communication between party A and party B. Party L then obtains Xa from the escrow center and public values Ya and Yb associated with the communication session that party L desires to gain access to. For example, party L eavesdrops directly on the exchange which was done without encryption. In one method, party L calculates secret key Kab using the equation Kab=Yb(Xa+n)mod p. Party L selects a value for n, such as 0 or some other value. Party L calculates Kab and tries to access the desired communication session. If unsuccessful, party L then changes n, for example, by incrementing n by one from the previous value of n. Party L then recalculates Kab until party L is successful in acquiring Kab.
In another aspect, party L calculates secret key Kab using the same equation Kab=Yb(Xa+n)mod p, but by first obtaining n from the equation Y=g(Xa+n)mod p. In one embodiment, party L sets n equal 0, calculates Y, then compares Y to Ya. If Y does not equal to Ya, party L changes n, for example, by incrementing n by one from a previous value of n. Party L then recalculates Y until Y equals Ya. When Y equals Ya, party L has acquired the value for n, and then calculates Kab=Yb(Xa+n)mod p with the acquired n and the previously known values of Yb and Xa.
After time period t has elapsed, a new value Xa is derived and escrowed with the escrow agent. Time period t can be based on the time between escrows or a value v such that a re-escrow is performed when n=v.

Method and apparatus for regenerating secret keys in Diffie-Hellman communication sessions


The magnetic actuator device of the invention comprises a magnetic field generator external to the duct and a permanent magnetic field generator internal to the duct, separated from the magnetic field generator external to the duct by a non-magnetic separator wall, and connected to a moving member, the permanent magnetic field generator internal to the duct being dimensioned to have a face spaced apart from the separator wall so as to define a space that can receive particles of metal without the actuator device jamming.

A magnetic actuator device for actuating a moving member in a duct is known, in particular from document FR-A-2 879 339, the actuator device comprising a magnetic field generator external to the duct and a permanent magnetic field generator internal to the duct, separated from the external magnetic field generator by a non-magnetic separator wall, and connected to the moving member. In known magnetic actuator devices, the permanent magnetic field generator internal to the duct is mounted to slide with small clearance relative to the facing separator wall. When the fluid for packaging contains particles of metal, as occurs with sugar-or chocolate-containing fluids manufactured from solid ingredients that have been subjected to grinding while being prepared, the particles are attracted by the magnetic field and they thus come to press against the separator wall in register with the internal magnetic field generator and on the face of the internal permanent magnetic field generator that faces towards said wall. During the reciprocating displacements of the permanent magnetic field generator internal to the duct, friction between the particles and the wall runs the risk of creating wear and also of blocking the moving member when the metal particles accumulate and are jammed between the permanent magnetic field generator internal to the duct and the facing wall.


An error checking system includes an input device for receiving a data element including parity information; a parity check device for checking the parity information of the data element to determine whether the data element is valid; a CRC generator coupled to the parity check device for generating a CRC for the data element; and an output device for transmitting the data element with the parity information and CRC to a downstream device over a transmission link. The parity check device is operative to output a corruption signal to the CRC generator if the parity check device determines that the data element is invalid, to instruct the CRC generator to corrupt the CRC generation for that data element.

As is known in the art, large host computers and servers (collectively referred to herein as "host computer/servers") require large capacity data storage systems. These large computer/servers generally include data processors, which perform many operations on data introduced to the host computer/server through peripherals including the data storage system. The results of these operations are output to peripherals, including the storage system.
One type of data storage system is a magnetic disk storage system. Here a bank of disk drives and the host computer/server are coupled together through an interface. The interface includes "front end" or host computer/server controllers (or directors) and "back-end" or disk controllers (or directors). The interface operates the controllers (or directors) in such a way that they are transparent to the host computer/server. That is, data is stored in, and retrieved from, the bank of disk drives in such a way that the host computer/server merely thinks it is operating with its own local disk drive. One such system is described in U.S. Pat. No. 5,206,939, entitled "System and Method for Disk Mapping and Data Retrieval", inventors Moshe Yanai, Natan Vishlitzky, Bruno Alterescu and Daniel Castel, issued Apr. 27, 1993, and assigned to the same assignee as the present invention.

Method of and system for error checking in a data storage system


A quick change drum for receiving and orienting pellet-like items in a pellet marking machine is disclosed. The quick change drum comprises a central shaft with two end plates perpendicularly attached to the ends of the shaft in parallel spaced apart relationship. A multiplicity of carrier bars are demountably attached to the end plates and span the space between the end plates forming a substantially continuous cylindrical surface. Each carrier bar has at least one concavity, preferably a multiplicity of concavities, disposed in its outwardly facing surface, the concavity or concavities being matched to a particular pellet-like item size and shape. The carrier bars are demountably attached to the end plates, preferably by bolts, but may also be attached by means of quick connect/disconnect devices which allow more rapid and efficient replacement of the carrier bars.

In the manufacture of many pharmaceutical products such as pills or lozenges, candies such as "M&M's", small mechanical parts such as ball bearings or electrical components such as resistors or capacitors, it is often desirable to imprint a trademark, indicia or other information or intelligence on each item. These products share a common characteristic in that they are all pellet-like items, being small, often round or rounded, oval, bulbous, cylindrical or polygonal in shape. Examples of pellet-like items are pills, lozenges, capsules, tablets and caplets.
Imprinting indicia on a series of pellet-like items is conveniently accomplished by a machine which receives a large number of items in bulk, typically from a feed hopper or bin, orients the items to a uniform relative orientation, conveys the oriented items to a printing unit wherein the indicia are applied to each item and discharges the items for subsequent packaging. U.S. Pat. No. 2,859,689 to Ackley is a typical example of a pellet marking machine which performs the steps outlined above. Pellet-like items, designated "P" in FIG. 2 of the '689 patent, are loaded in bulk into the feed hopper 22 where the items are received by a rotating drum or cylinder roll 23. The drum has a multiplicity of concavities or recesses 33 in its outwardly facing surface formed in accordance with the shape and size of the pellet-like items being processed. The items P are received into the concavities 33 as the drum rotates clockwise beneath hopper 22, retained in the concavities by cylindrical retainer surface 50 as the drum rotates and released to an endless conveyor 24 located beneath the drum, the conveyor having a multiplicity of individual carrier bars 110. Carrier bars 110 have corresponding concavities matching the concavities 33 in drum 23, and conveyor 24 is synchronized with drum 23 so that the matching concavities on the drum and the conveyor line up as the drum rotates clockwise and the conveyor circulates counterclockwise. Items P drop from concavities 33 in drum 23 into the matching concavities in the endless conveyor 24 once the items are clear of retaining surface 50. The pellet-like items P are then conveyed to a printing roller 27 which has ink laden images of the indicia or intelligence to be imprinted on the items circumferentially arrayed on its peripheral surface. Printing roller 27 rotates clockwise in synchronization with endless conveyor 24 and contacts the pellet-like items P as they pass beneath the printing roller 27, applying the ink laden image to each pellet-like item. After passing beneath printing roller 27, the pellet-like items P are discharged from conveyor 24 as the conveyor rounds its drive sprocket and the carrier bars 110 are momentarily vertically oriented.
Although pellet marking machines similar to that described in the '689 patent provide an effective means for reliably and rapidly marking pellet-like items with indicia, the machines are expensive and lack versatility, largely due to the design of rotating drum 23.
The drums are expensive because they are typically manufactured from a single custom made centrifugal casting which can weigh in excess of 350 lbs. This monolithic design has traditionally been thought necessary for drum manufacture in order to create a shell structure with a precision made, continuous outer surface which simultaneously allows access to the back surface of the shell for the mounting of auxiliary systems, such as vacuum assist systems to retain the pellet-like items to the drum as they are received from the hopper. The concavities are machined into the casting's curved outer surface, and machining such a heavy, monolithic piece is complicated, expensive, time consuming and risky. Complications arise because it is inherently more difficult to perform precision machining on a curved surface as compared with a flat surface, for example. The machining process is more expensive because often special tooling or jigs must be designed and fabricated to hold the heavy, bulky drum within the milling machine. The process is time consuming because of the typically large number of concavities which must be machined into a drum surface, requiring the drum to be constantly repositioned by the machinist on the milling machine so that the milling tool can have access to a tangent region on the drum surface. The process is risky because a single machining error can render the entire casting useless, perhaps negating many man-hours of machining effort, wasting thousands of dollars in material costs, as well as having an adverse impact on the production schedule for the machine.
In the recent past, pellet marking machine versatility was not a concern because there were a relatively limited number of pellet shapes and sizes in the marketplace and manufacturers by and large were satisfied with a dedicated machine for a particular product line. However, as the various industries, most notably pharmaceuticals, evolved over time, pellet marking machine versatility became more important. To remain competitive in the marketplace, pellet marking machines have been forced to evolve to keep up with the faster pace of technological change in product development, encapsulation methods, marking methods and packaging requirements, in addition to meeting the needs for greater efficiency and lower cost imposed by the highly competitive markets. In this context, pellet marking machine versatility, as evidenced by the ability to process different types of pellet-like items, has come to the fore as the desirable characteristic which makes one pellet marking machine superior to another among the various industrial customers.
The pellet marking machines of the past lack versatility because a monolithic drum can only have one type of concavity with a predetermined size and shape machined into its outer surface. The concavities in the monolithic drum must be specifically matched in size and shape to the particular pellet-like item being processed. Matching the concavity to the item is important for efficient processing of the items by the machine. Items which are poorly matched to their receiving concavities will not be efficiently received from the hopper, reducing the efficiency and item throughput of the machine as some concavities will fail to pick up an item as they pass beneath the hopper. The empty concavities have no item to transfer to the conveyor as the drum rotates through its cycle, resulting in an empty conveyor cavity passing beneath the printing rollers. Items which are received into concavities on the drum but which are not consistently positioned and reliably held due to shape or size mismatch between the items and the concavities will not be reliably and consistently transferred to the conveyor. Items not positioned precisely on the conveyor will not be correctly imprinted when the items pass beneath the printing roller, resulting in an unacceptable product and costly wastage. Some products may not make it to the printing roller at all and could even end up rolling loose on the conveyor, falling from the conveyor onto the factory floor or into the machine and fouling its moving parts.
Thus, if it is desired to process more than one type of pellet-like article with the same machine, a separate monolithic drum must be made to match to each type of item. Due to the size and weight of the monolithic drum and its position within the machine, a significant part of the machine must be disassembled to effect the change over to the new drum. The change over can require significant manpower as it is difficult for one person to safely handle a heavy drum and can further entail significant machine down time, adversely affecting item production rates and schedules. Furthermore, if a monolithic drum becomes damaged, it cannot be readily repaired in situ. Repair will typically require extensive machine down time to disassemble the machine and remove the drum for repair or replacement. Clearly, there is a need for an improved drum design in pellet marking machines which will increase versatility and efficiency of the machines while reducing the cost and risks associated with machine manufacture.


Described herein are biological devices and methods for using the same to produce oxidized zinc. The biological devices include microbial cells transformed with a DNA construct containing genes for producing a zinc-related protein, an alkaline phosphatase, and an alcohol dehydrogenase. In some instances, the biological devices also include a gene for lipase. The oxidized zinc compositions produced herein have numerous applications.

Zinc oxide is widely used across a variety of industries. Its ultraviolet-absorbing properties have been exploited in materials such as paints and coatings, plastics, and even sunscreen creams. Zinc oxide is employed industrially in the curing and vulcanization of rubber and latex, to impart heat resistance and abrasion resistance to rubber and plastic products, and in the medical industry in applications from wound healing to dental cement. Further, zinc oxide is a precursor material for other zinc salts including zinc diacrylate (used in the manufacture of golf balls), zinc chromate (used for anti-corrosion purposes), zinc borate and zinc chloride (used as flame retardants), zinc gluconate (used in cold-prevention lozenges and sprays), and zinc dithiophosphate (an anti-wear ingredient in lubricants), among others.
Production of zinc oxide can be expensive. Zinc ores must first be ground and sometimes roasted to produce zinc oxide. Sulfur dioxide is a typical byproduct of the process of roasting zinc ores; when this compound is released into the atmosphere, it contributes to acid rain. Toxic cadmium vapor is another byproduct of zinc refining, and further, zinc mining operations can lead to significant levels of heavy metal pollution in the air, in soil, and in waterways, causing concerns for human health, agriculture, and wildlife. Furthermore, the use of impure sources of zinc can lead to impurities and discoloration in the final product, affecting its use as a pigment, and can cause material to aggregate in processing furnaces and other equipment, reducing the life time of said equipment. Finally, although zinc oxide is non-toxic, fumes such as those generated when zinc and/or zinc alloys are vaporized or melted and oxidized can be quite hazardous, as well.
What is needed is a new method for producing oxidized zinc. Ideally, the method would be inexpensive to conduct and would work with a variety of starting materials including recycled materials and impure zinc sources. Furthermore, the method would not require the use of harsh chemicals or high-temperature furnaces and would generate fewer health and environmental hazards than traditional methods for producing zinc oxide.

Biological devices for producing oxidized zinc and applications thereof


Antitumor compounds have the five membered fused ring ecteinascidin structure of the formula (XIV). The present compounds lack a 1,4-bridging group as found in the ecteinascidins. They have at the C-1 position a substituent selected from an optionally protected or derivatised aminomethylene group or an optionally protected or derivatised hydroxymethylene group

European Patent 309,477 relates to ecteinascidins 729, 743, 745, 759A, 759B and 770. The ecteinascidin compounds are disclosed to have antibacterial and other useful properties. Ecteinascidin 743 is now undergoing clinical trials as an antitumour agent.
Ecteinascidin 743 has a complex tris(tetrahydroisoquinolinephenol) structure of the following formula (I):

In ecteinascidin 743, the 1,4 bridge has the structure of formula (IV):

Other known ecteinascidins include compounds with a different bridged cyclic ring system, such as occurs in ecteinascidin 722 and 736, where the bridge has the structure of formula (V):
ecteinascidins 583 and 597, where the bridge has the structure of formula (VI):
and ecteinascidin 594 and 596, where the bridge has the structure of formula (VII):

The complete structure for these and related compounds is given in J. Am. Chem. Soc. (1996) 118, 9017-9023. This article is incorporated by reference.
The ecteinascidins are currently prepared by isolation from extracts of the marine tunicate Ecteinascidin turbinata. The yield is low, and alternative preparative processes have been sought.
A synthetic process for producing ecteinascidin compounds is described in U.S. Pat. No. 5,721,362, see also WO 9812198. The claimed method is long and complicated. By way of illustration, there are 38 Examples each describing one or more steps in the synthetic sequence to arrive at ecteinascidin 743.
Claim 25 of U.S. Pat. No. 5,721,362 is directed at an intermediate phenol compound of a given formula (11), which we refer to also as Intermediate 11 or Int-11. It has the following bis(tetrahydroisoquinolinephenol) structure (II):
where MOM is a methoxymethyl substituent and TBDPS is a tert-butyldiphenylsilyl substituent.
From Intermediate 11 it is possible to synthesise another interesting antitumour agent, phthalascidin, see Proc. Natl. Acad. Sci. USA, 96, 3496-3501, 1999. Phthalascidin is a bis(tetrahydroisoquinolinephenol) derivative of formula (III):

More generally, phthalascidin and related compounds are described in WO 0018233. Claim 1 is directed at compounds of formula:
wherein the substituent groups defined by R1, R2, R3, R4, R5, R6, R7, R8 and R9 are each independently selected from the group consisting of H, OH, OR′, SH, SR′, SOR′, SO2R′, NO2, NH2, NHR′, N(R′)2, NHC(O)R′, CN, halogen, ═O, C(═O)H, C(═O)R′, CO2H, CO2R′, C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted aralkyl, and substituted or unsubstituted heteroaromatic;wherein each of the R′ groups is independently selected from the group consisting of H, OH, NO2, NH2, SH, CN, halogen, ═O, C(═O)H, C(═O)CH3, CO2H, CO2CH3, C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, aryl, aralkyl, and heteroaromatic;wherein each dotted circle represents one, two or three optional double bonds;wherein R7 and R8 may be joined into a carbocyclic or heterocyclic ring system;and wherein X1 and X2 are each independently defined as above for R1-R8 and further include various permitted definitions.
Further naturally occuring compounds are known which lack a bridged cyclic ring system. They include the bis(tetrahydroisoquinolinequinone) antitumor-antimicrobial antibiotics safracins and saframycins, and the marine natural products renieramicins and xestomycin isolated from cultured microbes or sponges. They all have a common dimeric tetrahydroisoquinoline carbon framework. These compounds can be classified into four types, types I to IV, with respect to the oxidation pattern of the aromatic rings.
Type I, dimeric isoquinolinequinones, is a system of formula (VIII) most commonly occurring in this class of compounds, see the following table I.
TABLE IStructure of Type I Saframycin Antibiotics. SubstituentsCompoundR14aR14bR21R25aR25bR25csaframycin AHHCNOOCH3saframycin BHHHOOCH3saframycin CHOCH3HOOCH3saframycin GHOHCNOOCH3saframycin HHHCNOHCH2COCH3CH3saframycin SHHOHOOCH3saframycin Y3HHCNNH2HCH3saframycin Yd1HHCNNH2HC2H5saframycin Ad1HHCNOOC2H5saframycin Yd2HHCNNH2HHsaframycin Y2bHQbCNNH2HCH3saframycin Y2b–dHQbCNNH2HC2H5saframycin AH2HHCNHaOHaCH3saframycin AH2AcHHCNHOAcCH3saframycin AH1HHCNOHaHOCH3saframycin AH1AcHHCNOAcHCH3saframycin AR3HHHHOHCH3aassignments are interchangeable.bwhere the group Q is of formula (IX):
Type I aromatic rings are seen in saframycins A, B and C; G and H; and S isolated from Streptomyces lavendulae as minor components. A cyano derivative of saframycin A, called cyanoquinonamine, is known from Japanese Kokai JP-A2 59/225189 and 60/084,288. Saframycins Y3, Yd1, Ad1, and Yd2 were produced by S. lavendulae by directed biosynthesis, with appropriate supplementation of the culture medium. Saframycins Y2b and Y2b-d dimers formed by linking the nitrogen on the C-25 of one unit to the C-14 of the other, have also been produced in supplemented culture media of S. lavendulae. Saframycins AR1 (=AH2,), a microbial reduction product of saframycin A at C-25 produced by Rhodococcus amidophilus, is also prepared by nonstereoselective chemical reduction of saframycin A by sodium borohydride as a 1:1 mixture of epimers followed by chromatographic separation [the other isomer AH1 is less polar]. The further reduction product saframycin AR3. 21-decyano-25-dihydro-saframycin A. (=25-dihydrosaframycin B) was produced by the same microbial conversion. Another type of microbial conversion of saframycin A using a Nocardia species produced saframycin B and further reduction by a Mycobacterium species produced saframycin AH1Ac. The 25-O-acetates of saframycin AH1 and AH1 have also been prepared chemically for biological studies.
Type I compounds of formula (X) have also been isolated from marines sponges, see Table II.
TABLE IIStructures of Type I Compounds from Marine Sponges. SubstituentsR14aR14bR21Rrenieramycin AOHHH—C(CH3)═CH—CH3renieramycin BOC2H5HH—C(CH3)═CH—CH3renieramycin COHOO—C(CH3)═CH—CH3renieramycin DOC2H5OO—C(CH3)═CH—CH3renieramycin EHHOH—C(CH3)═CH—CH3renieramycin FOCH3HOH—C(CH3)═CH—CH3xestomycinOCH3HH—CH3
Renieramycins A-D were isolated from the antimicrobial extract of a sponge, a Reniera species collected in Mexico, along with the biogenetically related monomeric isoquinolines renierone and related compounds. The structure of renieramycin A was initially assigned with inverted stereochemistry at C-3, C-11, and C-13. However, careful examination of the 1H NMR data for new, related compounds renieramycins E and F, isolated from the same sponge collected in Palau, revealed that the ring junction of renieramycins was identical to that of saframycins. This result led to the conclusion that the formerly assigned stereochemistry of renieramycins A to D must be the same as that of saframycins.
Xestomycin was found in a sponge, a Xestospongia species collected from Sri Lancan waters.
Type II compounds of formula (XI) with a reduced hydroquinone ring include saframycins D and F, isolated from S. lavendulae, and saframycins Mx-1 and Mx-2, isolated from Myxococcus xanthus. See table III.
TABLE IIIType II Compounds SubstituentsCompoundR14aR14bR21R25aR25bR25csaframycin DOOHOOCH3saframycin FOOCNOOCH3saframycin Mx-1HOCH3OHHCH3NH2saframycin Mx-2HOCH3HHCH3NH2
The type III skeleton is found in the antibiotics safracins A and B, isolated from cultured Pseudomonas fluorescens. These antibiotics of formula (XII) consist of a tetrahydroisoquinoline-quinone subunit and a tetrahydroisoquninolinephenol subunit.
where R21 is —H in safracin A and is —OH in safracin B.
Saframycin R, the only compound classified as the Type IV skeleton, was also isolated from S. lavendulae. This compound of formula (XIII), consisting of a hydroquinone ring with a glycolic ester sidechain on one of the phenolic oxygens, is conceivably a pro-drug of saframycin A because of its moderate toxicity.

All these known compounds have a fused system of five rings (A) to (E) as shown in the following structure of formula (XIV):

The rings A and E are phenolic in the ecteinascidins and some other compounds, while in other compounds, notably the saframycins, the rings A and E are quinolic. In the known compounds, the rings B and D are tetrahydro, while ring C is perhydro.


The invention relates to an improved electro-dynamic loudspeaker. The electro-dynamic loudspeaker comprises (a) a voice coil for generating an acoustic waveform, the voice coil being longitudinally movable from an initial rest position to generate the acoustic waveform; (b) a second element of the loudspeaker, the second element being stationary relative to the voice coil; (c) an inductance-affecting core mounted on the voice coil for movement therewith, the inductance-affecting core having a length and a variable inductance-affecting capacity; (d) at least one inductor adjoining the inductance-affecting core and mounted on the second element, the at least one inductor having an associated length shorter than the length of the conductor core such that only a variable portion of the inductance-affecting core adjoins the inductor, the variable portion having a variable average inductance-affecting capacity and a portion length substantially equal to the associated length of the at least one inductor; and, (e) a position sensor circuit connected to the at least one inductor for providing a variable signal based on the variable average inductance-affecting capacity of the variable portion of the inductance-affecting core adjoining the at least one inductor. The variable average inductance-affecting capacity of the variable portion varies with the degree of deflection of the voice coil relative to the second element to vary the variable signal.

The construction and operation of electro-dynamic loudspeakers are well known. The physical limitations in their construction are one cause of non-linear distortion, which is sensible in the generated sound production. Distortion is particularly high at low frequencies, in relatively small sealed box constructions where cone displacement or excursions are at their maximum limit.
In the past, one of many approaches taken to reduce speaker distortion has been to use motional feedback to compensate for this distortion. Motional feedback controls frequency response and reduces non-linear distortions. Motional feedback is usually implemented using accelerometers, velocity sensors and/or position sensors. In the past, accelerometers have been the most successful, as they are inexpensive and their performance does not depend on the extent of displacement, thereby contributing to the linearity of the output signal. The linearity of any sensor is critical in audio applications, as even very strong feedback cannot reduce distortions beyond those introduced by the sensor itself.
Despite the advantages afforded by the linearity of their output, accelerometers have problems of their own. At low frequencies, the distortions generated by typical speakers are very high. Some components of these distortions can move the speaker cone from its optimal, center position; however, accelerometers will be blind to slow shift in cone position and their output signals will not include information that can be sent back to the amplifier to correct for this slow shift. Similarly, velocity sensors will be blind to cone position.
Position sensors do not suffer from these shortcomings. However, like velocity centers, the operation of position sensors requires two elements to be moved relative to each other. This makes their operation sensitive to cone excursion. Consequently, the signals provided by each will not be linear, particularly at large displacements
Thus, there is a need to measure slow shift and cone position. Both accelerometers and velocity sensors are unable to provide this measurement. Position sensors can provide this measurement; however, such sensors themselves create non-linearities. Position sensors that measure the variations in coil induction are generally considered to be the most practical, reliable and least sensitive to the environment of available position sensors. However, such position sensors still suffer from these problems. Existing sensors of this kind typically include multiple coils mounted coaxially with a voice coil of a speaker. A conductive element such as a metal rod or another coil moves inside the external coils. An electrical circuit converts the movement of the interior conductive element in the exterior coil to an electrical signal. However, as described above, the conversion of the displacement to voltage may not be linear, especially for large displacements. In addition, as the coils are mounted coaxially with the speaker voice coil, additional voltages may be induced in the voice coils thereby generating noise.
Accordingly, there is a need for a position sensor that is inexpensive, easy to build, provides a linear output and minimizes the generation of voltage noise in the speaker voice coil.


A quick change tooling method and apparatus has been devised for tube bending operations in which the bend die, clamp die and pressure die as well as mandrel and wiper die, if required, are preassembled along with a tube corresponding to the tube to be bent in that particular die assembly by releasable latches or other types of releasable connectors; and each preassembled die set as described can be removed, transported and relocated on a bending machine as a complete assembly and in exact aligned operating position without readjustment and pressure setting each time that the die set is installed. A lift mechanism is provided to facilitate lifting of each die set onto and from the bending machine as well as to automatically locate each die set in proper aligned position on the machine.

This invention relates to tube bending apparatus, and more particularly relates to a novel and improved method and apparatus for quickly and accurately changing die sets for different-sized tubing to be bent or for different types of tube bending operations.
Tube bending operations require precise alignment between a bend die, pressure die and clamping die for each size of tube to be bent. In many cases, a wiper die is required along with a mandrel which is inserted into the tube portion to be bent. In the standard bending operation, holders are provided on the bend die table which are movable into engagement with the bend and clamping dies, and the pressure die is advanced linearly as the bend die is rotated with the tube to be bent being securely clamped in complementary grooves therebetween to undergo bending and assume the configuration of the grooves as pressure is applied. In many tube bending operations, a mandrel must be inserted into the tube to be bent in order to prevent wrinkling or collapse of the portion of the tube being bent; and in many cases, a wiper die is employed in cooperation with the pressure die to regulate the pressure applied to the tubing during the bending operation.
In changing the various dies for different-sized tubing, the standard practice has been to individually remove the dies and reassemble a new die set onto the table which is time-consuming and results in considerable downtime. In certain tube bending applications, it has been proposed to be able to remove more than one component part of the die set in one step or to provide special devices to facilitate replacement of the die set in an effort to reduce downtime and, for example, reference is made to U.S. Pat. Nos. 4,178,788 to R. T. Zollweg et al, 4,355,525 to J. W. Carson, 4,967,585 to S. Grimaldo, 5,148,695 to H. S. Ellis, 5,339,670 to A. Granelli, 5,426,965 to W. G. Hopf and 5,499,521 to M. E. Luikart et al. Nevertheless, to the best of our knowledge, no one has devised a one-step operation in which component dies of the tube bending apparatus can be removed from the bending table and stored in assembled form so as to retain the same precise alignment and relationship established from the previous bending operation. In this way, the apparatus can be remounted on the table as one unit and remain in the desired relationship so as not to require extensive set-up time in preparing for the next bending operation for that particular sized tubing; and further wherein the die set or kit is so assembled and arranged as to facilitate automated removal and reinstallation with respect to a standard die table as well as the ability to rapidly and accurately locate one or more die sets at one time with respect to the bend die table.

Quick change tooling method and apparatus


A system and method for recommending and installing scheduled delivery (SD) print applications is disclosed. In one example, one or more SD print applications are determined based on prior usage of SD print applications in a printer application store by a user of a web connected computing device. Further, the determined one or more SD print applications are recommended by sending a notification to the web connected computing device and then to a web connected printer via an electronic messaging service.

Typically, a printer application store includes a variety of scheduled delivery (SD) print applications related to various categories, such as sports, news, horoscopes and the like. To install a SD print application, a user may have to login to the printer application store using login credentials, such as a username and password, via a web connected computing device, such as a personal computer (PC), a tablet, a mobile device and the like. After logging in, one or more keywords describing a category of SD print application is entered. Based on the keywords entered, the printer application store lists out various SD print applications. Then, one or more SD print applications of interest can be selected from the list using the web connected computing device and installed for a web connected printer.
However, the number of SD print applications available in a printer application store, in each category, can be enormous. The sheer quantity of the SD print applications available can make it difficult and time consuming to find relevant and interesting SD print applications. This may detract from the overall user experience.
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

Recommending and installing scheduled delivery print applications

HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.