An apparatus for modulating information bearing symbols onto an optical carrier includes a polybinary coder that operates on a binary information signal to produce an envelope compatible polybinary signal; and an optical single sideband modulator that modulates an optical carrier with the envelope compatible polybinary signal to produce a single sideband optical signal. This provides an improvement over both polybinary signaling and optical single sideband. This action combines the chromatic dispersion advantages of SSB modulation with the DC level and bandwidth reduction of duo-binary coding.

Optical fiber transmission systems are subject to distortion related to loss, noise, and nonlinearities in both the fiber and the modulation and amplification devices. One of the more deleterious forms of signal distortion is that due to chromatic dispersion. Chromatic dispersion in optical fiber is typically characterized by a linear (non-flat) group delay parameter. The group refractive index of the fiber at optical frequencies near a given optical carrier frequency varies approximately linearly with wavelength or optical frequency about the carrier. This finite linear group delay imposes a quadratic phase rotation across the signal frequency band which translates to intersymbol interference in the time domain signal. The fact that a large portion of the fiber in use today is dispersive at the desired operating wavelengths dictates that economic solutions are required.
Approaches currently used to reduce the effects of chromatic dispersion include: (1) reversing the effects of chromatic dispersion in the optical domain, (2) reversing the effects in the electrical domain after optical detection and (3) reducing the transmission bandwidth of the optical signal on the fiber. The first is based on purely optical methods where the effects of group velocity dispersion are reversed while the signal is still in the optical domain. Adding dispersion compensating fiber in the transmission path is one common approach. Other optical methods include compensation by differential time delay of the upper and lower sidebands of the modulated signal, see A. Djupsjobacka, O. Sahlen, xe2x80x9cDispersion compensation by differential time delay,xe2x80x9d IEEE Journal of Lightwave Technology, vol. 12, no. 10, pp. 1849-1853, October 1994, spectrally inverting the signal at the midpoint of the transmission path, see R. M. Jopson, A. H. Gnauck, R. M. Derosier, xe2x80x9c10 Gb/s 360-km transmission over normal-dispersion fiber using mid-system spectral inversion,xe2x80x9d Proceedings OFC""93, paper PD3, 1993; and pre-chirping the transmitted signal in an external modulator, see F. Koyama, K. Iga, xe2x80x9cFrequency chirping in external modulators,xe2x80x9d IEEE Journal of Lightwave Technology, vol. 6, no. 1, pp. 87-03, January 1988, and A. H. Gnauck, S. K. Korotky, J. J. Veselka, J. Nagel, C. T. Kemmerer, W. J. Minford, D. T. Moser, xe2x80x9cDispersion penalty reduction using an optical modulator with adjustable chirp,xe2x80x9d IEEE Photonics Technology Letters, vol. 3, no. 10, pp. 916-918, October 1991.
The second approach, in which dispersion effects are reversed in the electrical domain, is based on coherent transmission and homodyne detection followed by equalization in the electrical domain. Homodyne detection is only effective on single sideband signals. If homodyne detection were attempted with a DSB signal, the upper and lower sidebands would overlap upon detection and the phase information would be lost and the higher modulation frequencies severely attenuated or distorted through frequency selective fading. Some techniques used or proposed for post-detection equalization include the use of microstrip lines, see K. Iwashita, N. Takachio, xe2x80x9cChromatic dispersion compensation in coherent optical communications,xe2x80x9d Journal of Lightwave Technology, vol. 8, no. 3, pp. 367-375, March 1990; microwave waveguides, see J. H. Winters, xe2x80x9cEqualization in coherent lightwave systems using microwave waveguides,xe2x80x9d Journal of Lightwave Technology, vol. 7, no. 5, pp. 813-815, May 1989, and fractionally spaced equalizers, see J. H. Winters, xe2x80x9cEqualization in coherent lightwave systems using a fractionally spaced equalizer,xe2x80x9d Journal of Lightwave Technology, vol. 8, no. 10, pp. 1487-1491, October 1990.
The third approach is to modify the transmission format so that the baseband signal spectrum is compressed. These types of approaches, which reduce the transmission bandwidth required on the fiber to transmit a given bit rate, are generally implemented by modifying the line code format in order to reduce the effective bandwidth required to transmit or receive the data, see K. Yonenaga, S. Kuwano, S. Norimatsu, N. Shibata, xe2x80x9cOptical duobinary transmission system with no receiver sensitivity degradation,xe2x80x9d Electronic Letters, vol. 31, no. 4, pp. 302-304, February 1995, and G. May, A. Solheim, J. Conradi, xe2x80x9cExtended 10 Gb/s fiber transmission distance at 1538 nm using a duobinary receiver,xe2x80x9d IEEE Photonics Technology Letters, vol. 6, no. 5, pp. 648-650, May 1994.
More recently it has been shown that optical single sideband transmission (OSSB) can combat some of the deleterious effects of chromatic dispersion. OSSB provides a dispersion benefit directly by reducing the signal bandwidth and also by aiding in the signal restoration through post-detection dispersion compensation. The generation, transmission and detection of single sideband (SSB) signals has been used for both baseband and the RF and microwave regions of the electromagnetic spectrum to reduce the bandwidth of the signal by a factor of two, by sending either the upper or the lower sideband. Generation and transmission of OSSB optical signals using a Mach-Zehnder modulator is shown in M. Izutsu, S. Shikama, T. Sueta, xe2x80x9cIntegrated optical SSB modulator/frequency shifter,xe2x80x9d IEEE Journal of Quantum Electronics, vol. QE-17, no. 11, pp. 2225-2227, November 1981, and R. Olshansky, xe2x80x9cSingle sideband optical modulator for lightwave systems,xe2x80x9d U.S. Pat. No. 5,301,058, 1994. Methods based on AM compatible radio modulators were outlined in Jan Conradi, Bob Davies, Mike Sieben, David Dodds and Sheldon Walklin, xe2x80x9cOptical Single Sideband (OSSB) Transmission for Dispersion Avoidance and Electrical Dispersion Compensation in Microwave Subcarrier and Baseband Digital Systemsxe2x80x9d, OFC 97 Postdeadline, February 1997, and M. Sieben, J. Conradi, D. Dodds, B. Davies, and S. Walklin xe2x80x9c10 Gbit/s optical single sideband systemxe2x80x9d Electronics Letters Vol. 33, No. 11, pp 971-973. Sieben; Michael J., Conradi; Jan, Dodds; David E., U.S. Pat. No. 5,880,870, Mar. 9, 1999 Optical modulation system Robert J. Davies, Jan Conradi, David Dodds, Hybrid Single Sideband Optical Modulator. U.S. Pat. No. 5,999,300, Dec. 7, 1999., and Robert J. Davies, Minimum Phase Dispersion Compensator, U.S. Pat. No. 5,949,926, Sep. 7, 1999. The structures outlined in these documents addressed the need for large added carrier in the transmitted optical signal by using approximations to time domain minimum phase signals with single sideband properties. This allowed the transmitted information to be directly modulated onto the optical electric field envelope while a special phase function was incorporated into the AM signal to cancel all or part of an information sideband.
While in digital optical SSB modulation a dispersion benefit accrues directly due to the fact that the transmitted signal spectrum has been reduced, the more significant advantage of optical SSB transmission is that the fiber dispersion can be compensated in the electrical domain after detection. This advantage is similar to that for heterodyne detection of DSB signals, but with SSB transmission and detection, the signal can be homodyned directly to baseband using carrier signal added either at the source or at the receiver and thus it can be directly detected with the phase or delay information of the transmitted signal preserved. This was shown in K. Yonenaga, N. Takachio, xe2x80x9cA Fiber chromatic dispersion compensation technique with an optical SSB transmission in optical homodyne detection systems,xe2x80x9d IEEE Photonics Technology Letters, vol. 5, no. 8, pp. 949-951, August 1993, where integrated optical structures were used to generate single sideband tones for narrowband applications. In K. Yonenaga, N. Takachio, xe2x80x9cDispersion compensation for homodyne detection systems using a 10 Gb/s optical PSK-VSB signal,xe2x80x9d IEEE Photonics Technology Letters, vol. 7, no. 8, pp. 929-931, August 1995, a single sideband optical modulator was described for the purpose of transmitting two or more optical signals with different optical carrier frequencies on a single fiber. The purpose of transmitting the signals in a single sideband format is to permit these optical carrier frequencies to be spaced as closely as the maximum modulation frequency. A fundamental disadvantage of this type of dispersion compensation is found in the fact that the carrier power added to the transmitted signal must be significant thus reducing the potential signal to noise ratio at the transmitter.
To improve this situation the virtues of polybinary (or duo-binary) modulation may be applied. The term polybinary refers to a modification of a binary signal in which the levels have been altered so as to maintain the information while removing some of the DC content of the signal and reducing the bandwidth. The most common implementation of this type of signal is the duobinary signal where a two level binary signal is converted to a three level signal represented by a zero voltage level and two levels symetrically located at positive and negative voltage levels with respect to the zero voltage level. The non-zero voltage level represent logical zeros and the zero level represents logical ones. These signals are part of a class of signals referred to as correlative coding or partial response signals, so named because they allow a controlled amount of inter-symbol interference to achieve another advantage such as reduced bandwidth and reduced dc content. See Lender, A., xe2x80x9cThe Duo-Binary Technique of High Speed Data Transmission.xe2x80x9d AIEE Transaction on Communication Electronics,xe2x80x9d vol. 82, pp 214-218.
The coding rule for a duobinary signal generated from a binary signal where a logical zero or a xe2x80x98spacexe2x80x99 is represented by xe2x88x921 and a logical one or a xe2x80x98markxe2x80x99 is represented by a +1 is given by
ck=bk+bkxe2x88x921xe2x80x83xe2x80x83(1)
where bk is the kth element of binary sequence defined above. The resulting 3 level sequence is called a duo-binary sequence and the data sequence bk may be recovered from ck by the following rule
bk=ckxe2x88x92bkxe2x88x921xe2x80x83xe2x80x83(2)
The immediate advantage of this type of signal is a reduced bandwidth requirement for a given information rate. The disadvantage is related to the fact that a single symbol error will propagate through the data sequence due to correlation between the symbols. To overcome this a precoding scheme may be used. In this case the binary information is unipolar in that a mark is represented as a 1 and a space is represented as a 0. An intermediate pre-coded sequence is generated as in
xe2x80x83ak=bk⊕akxe2x88x921xe2x80x83xe2x80x83(3)
where ⊕ denotes modulo-2 addition. The precoder output is scaled so that a space is represented as a xe2x88x921 and a mark is represented as a +1. The precoded sequence is used to produce the duobinary sequence according to (1) above (ck=ak+akxe2x88x921) with the added advantage that the duobinary sequence so generated has independent symbols and is immune to error propagation. The data may be recovered in envelope detection format by simply determining the magnitude of the duobinary signal and scaling so that the recovered data sequence is represented by 1xe2x80x2s and 0xe2x80x2s as in                                           b            ^                    k                =                  {                                                                      0                                                                                1                    ,                                                                                "LeftBracketingBar"                                              c                        k                                            "RightBracketingBar"                                         greater than                     1                                                                                "LeftBracketingBar"                                              c                        k                                            "RightBracketingBar"                                        ≤                    1                                                                                (        4        )
A sample data sequence with precoding and duobinary encoding is shown in Table 1.
The information sequence bk is mapped into ck such that the individual symbols are independent and the bandwidth requirement for a given information rate is halved. Other types of correlative coding are possible if the coding rule is allowed to be more complicated. Some of these more complicated schemes are known as modified duobinary and alternate mark inversion. Additionally a binary signal may be mapped into a multilevel or polybinary signal where there are 5, 7 or more amplitude levels.
The spectral density function of the duo-binary signal based on the coding rule above is given by                               H                                (            f            )                          =                  {                                                                      2                                                        cos                                                              (                                              π                                                                          xe2x80x83                                                                        f                                                                          xe2x80x83                                                                                T                          b                                                                    )                                                                                exp                                                              (                                                                        -                          j                                                                                xe2x80x83                                                                        π                                                                          xe2x80x83                                                                        f                                                                          xe2x80x83                                                                                T                          b                                                                    )                                                                                "LeftBracketingBar"                    f                    "RightBracketingBar"                                    ≤                                      1                                          2                                                                    T                        b                                                                                0                                            otherwise                                                                        (        5        )
From the optical direct detection perspective, the reduction of the dc component compared to the binary case and the bandwidth reduction inherent in duobinary coding are the most favourable benefits of duobinary signaling along with the fact that the signal is recoverable by envelope detection. Complete removal of the dc component may be achieved for a different coding rule known as modified duo-binary. In this case the precoder rule is given by
ak=bk⊕akxe2x88x922xe2x80x83xe2x80x83(6)
and the correlation span for the coder is 2 digits rather than 1 as in
ck=akxe2x88x92akxe2x88x922xe2x80x83xe2x80x83(7)
Table 2 shows the modified duobinary coding method.
The spectral density for the modified duo-binary coding rule is given by                               H                                (            f            )                          =                  {                                                                      2                                    j                                                        xe2x80x83                                                                          sin                                                              (                                              π                                                                          xe2x80x83                                                                        f                                                                          xe2x80x83                                                                                T                          b                                                                    )                                                                                exp                                                              (                                                                        -                          j                                                                                xe2x80x83                                                                        π                                                                          xe2x80x83                                                                        f                                                                          xe2x80x83                                                                                T                          b                                                                    )                                                                                "LeftBracketingBar"                    f                    "RightBracketingBar"                                    ≤                                      1                                          2                                                                    T                        b                                                                                0                                            otherwise                                                                        (        8        )
where it is noted that the DC component is zero valued. Thus for a trade-off in coder length, an SNR advantage is gained in the sense that none of the finite power of the optical signal is wasted on the non-information carrying DC or carrier component of the signal.
For the polybinary case we may consider the case where a binary signal is converted into a signal with j levels that are numbered form 0 to jxe2x88x921. The coding rule in this case is given by
ak=bk⊕akxe2x88x921⊕akxe2x88x922⊕ . . . akxe2x88x92(jxe2x88x922)xe2x80x83xe2x80x83(9)
The precoded sequence is then converted to the j level signal using
ck=ak+akxe2x88x921+ . . . +akxe2x88x92(jxe2x88x922)xe2x80x83xe2x80x83(10)
where the spaces in the sequence xe2x80x98axe2x80x99 have been changed from zero to xe2x88x921. Note that the correlation span now covers a length of jxe2x88x921 digits. The demodulation rule is slightly more difficult than the duo-binary case in that marks are taken from the odd levels in the polybinary sequence and the spaces are taken from the even levels. Nonetheless the information is still recoverable using envelope detection techniques.
This invention provides an improvement over both polybinary signaling and optical single sideband by implementing polybinary modulation on a single sideband modulator. This action combines the chromatic dispersion advantages of SSB modulation with the DC level and bandwidth reduction of duo-binary coding.
Therefore there is provided an apparatus for modulating information bearing symbols onto an optical carrier, the apparatus comprising a polybinary coder that operates on a binary information signal to produce an envelope compatible polybinary signal; and an optical single sideband modulator that modulates an optical carrier with the envelope compatible polybinary signal to produce a single sideband optical signal.
In a further aspect of the invention, the polybinary coder produces an envelope compatible polybinary signal by dividing a polybinary signal into at least a pair of unipolar signals. In a further aspect of the invention, the polybinary coder produces an envelope compatible polybinary signal by separately operating on a polybinary signal in a first stream to convert all negative symbols in the polybinary stream to zero symbols and in a second stream to convert all positive symbols in the polybinary signal to zero symbols.
In a further aspect of the invention, the optical single sideband modulator operates on the optical carrier using the envelope compatible polybinary signal to produce a single sideband optical signal whose phase is determined by operating on the output of the polybinary coder with a Hilbert transform and whose magnitude is determined by the magnitude of the output of the polybinary coder. The output of the polybinary coder may be converted by a logarithmic operator prior to input to the Hilbert transform. The output of the polybinary coder may be adjusted to avoid singularities in the operation of the logarithmic operator.

Optical duobinary single sideband modulator


The apparatus employs a method for accurate, reproducible analytical solution evaluation eliminating the need for a reference sensor by determining the activity of selected species employing species specific sensors and species combination sensors in conjunction with Nernst-type equations. The apparatus includes sensor structures for elimination of edge effects to signals thereby yielding accurate, reproducible measurements, and a cartridge structure adapted to incorporate an array of the new sensors for employment of the new method where the cartridge is particularly adapted for miniaturization, maintaining a fixed volume of solution for analysis and providing an anaerobic testing environment. Lastly, a compact instrument embodying miniaturization especially adapted for field use and use of the cartridge is provided herein.

Traditional wet chemistry techniques in analytical chemistry and its use in the area of clinical chemistry have in the recent decades been improved. The improvements are based on the interaction of microprocessors with electromechanical devices that allow for these measurements to be made more precisely and easily.
In the subdiscipline of electrochemical measurements in the recent decade there has been considerable adaptation of the above methods to develop units that can self calibrate and measure the components in a sample. These units have been called cards or cartridges.
With the movement of chemistry tests outside the ambiance of a laboratory the need for these self contained test units for a wide variety of tests becomes important. Hence the need for a universal card or cartridge designed to be able to be modified at the factory to carry out a given range of tests which can work with one instrument becomes defined. At the factory the requisite range is fixed as according to customer requirements. Hence there will be cartridges that can carry out ionic profiles in soil or blood, and so on. To be able to carry out a wide range of tests it becomes important that the cartridge together with the instrument could lend themselves to a number of wet chemistry techniques ranging from electrochemical to optical methods.
The invention relates to a disposable universal sensor cartridge and an analyzer that can carry out a fixed range of tests that may use more than one method of analysis at the same time or different methods from time to time depending on the cartridge and the tests prescribed to it. Although the cartridge could work with a conventional reference electrode or source it specially lends itself for use with the comparator method developed by Guruswamy (patent application Ser. No. 07/008,554 to be U.S. Pat. No. 4,762,594 on Aug. 9, 1988) which does not require a reference electrode or source but rather a comparator electrode or source.
In clinical chemistry it is important for samples drawn from different parts of the body by devices ranging from "lancets" for finger pricks or finger sticks to acquire single drops of blood, to syringes for venous blood samples to be introduced easily into the cartridge with minimum contamination or evaporative loss from the sample. Our invention relates among other things to the drawing of blood from a punctured finger via a finger prick into the cartridge directly while allowing for other modes of introduction into the cartridge.
Most analytical systems are exposed to the ambient environment. They are not airtight. An airtight environment is desirable, first, to more closely match in-vivo conditions. Furthermore, it is important, for example, in blood gas analysis to avoid sample contamination from air so as to cause skewing of the results. This is particularly true in the analysis of blood gases but may pertain to measurement of other components as well. Lastly, to obtain a series of substance or component measurements from a sample, requires considerable time and many individual measurements. Not only is the time factor detrimental but, also, specimen contamination and chemical changes in the specimen are likely to occur. Hence, it is desirable to maintain an airtight measuring environment to achieve accurate measurements of certain substances, and most notably, blood gas concentrations. Lastly, most known systems do not contemplate fixing or providing fixed volume delivery. Elaborate stirring or mixing arrangements are used to insure uniform transport to the sensor. It would be desirable to conduct measurements of a fixed volume of solution and especially desirable to provide analysis requiring only a small volume of solution uniformly delivered to the sensor to make the measurements.
Other practical considerations arise relative to laboratory use by the clinician. In the event that a system is intended to be reusable, it is incumbent upon the operator or technician to insure that the electrodes are not contaminated when preparing for a test. Thorough cleaning and recalibration is necessary for each use. Such efforts require considerable labor and render cost ineffective the use of reusable systems especially in hospital laboratories or make inefficient their use in the field. Where disposable systems are employed, problems arise relating to the technician's reproducibility of the technique used.
Another aspect of electrochemical apparatus design and operation that has escaped attention in developments to date is the attribute of a compact, simply employable, field or laboratory use instrument which can be operated by persons having a minimum of skilled training. Miniaturized and standardized equipments are not available for providing analytical electrochemical measurements like those described above.

Universal sensor cartridge for use with a universal analyzer for sensing components in a multicomponent fluid


A speaker apparatus includes: an actuator serving as a source of vibration; a vibration transmitting member connected to the actuator; and two sheet-like diaphragms provided opposite to each other in the thickness direction thereof with the vibration transmitting member and disposed in contact with the vibration transmitting member, wherein vibration generated at the actuator is transmitted to each of the two diaphragms through the vibration transmitting member to output sounds.

There are speaker apparatus from which sounds are output by transmitting vibration generated at an actuator to a diaphragm through a vibration transmitting member. For example, the actuator used in such a manner may be a piezoelectric actuator, an electrostrictive actuator or the like. A material having high vibration transmitting characteristics may be used as the vibration transmitting member, and the diaphragm may be formed from, for example, a resin material such as an acrylic material.
In a speaker apparatus as thus described, when vibration generated at the actuator is transmitted to the diaphragm through the vibration transmitting member, a compressional wave is instantaneously propagated in the direction in which the vibration is transmitted (vibration exciting direction). During the propagation of the compressional wave, a force attributable to the Poisson's ratio of the solid body (diaphragm) is generated in a direction orthogonal to the vibration exciting direction. When the force in the direction orthogonal to the vibration exciting direction is generated, the force causes the diaphragm to vibrate, and sound waves are generated throughout the diaphragm to output sounds.
Therefore, in a speaker apparatus utilizing a vibration transmitting member and a diaphragm as thus described, sound waves are generated at a level that is uniform in any part of the diaphragm, and uniform acoustic characteristics can be achieved throughout the diaphragm.
Speaker apparatus of the above-described type include a speaker having an actuator disposed on one side of a cylindrical diaphragm when viewed in the axial direction of the diaphragm and a vibration transmitting member disposed in contact with one end face of the diaphragm when viewed in the axial direction of the diaphragm. Thus, vibration is transmitted to the end face of the diaphragm in the axial direction thereof to output sounds from the diaphragm (see JP-A-2007-166027 (Patent Document 1)).
In the speaker apparatus disclosed in Patent Document 1, when vibration is transmitted to the vibration transmitting member, a compressional wave is instantaneously propagated in the axial direction of the diaphragm. A force attributable to the Poisson's ratio of the diaphragm is generated in a direction orthogonal to the axial direction of the diaphragm to cause vibration of the diaphragm. Thus, sound waves are generated throughout the diaphragm, and sounds are output.


A wellhead stack assembly is provided that includes pressure restriction devices. The pressure restriction devices are staged such that each pressure restriction device is coupled to another pressure restriction device for cascading pressure differentials across the pressure restriction devices. Each pressure restriction device includes an active element positionable about a drill pipe for controlling a gap between the drill pipe and the active element.

A wellhead stack assembly can be mounted below a rig floor. A wellhead stack assembly includes pressure control devices, including but not limited to devices such as a rotating control device (RCD) and one or more blowout preventers, for sealing wellbore pressure from atmospheric pressure. Controlling and containing downhole pressures protects workers and equipment on the rig floor from wellbore pressure during a drilling operation. These devices can include seal elements that can wear from contact with a drill pipe and fluid from the wellbore.

Pressure staging for wellhead stack assembly


The invention concerns a method for treating and preventing secondary effects of hyperinsulinemia by application of insulin-like growth factor I (IGF I), and pharmaceutical compositions comprising IGF I which are useful for this purpose.

Insulin regulates blood glucose by
(a) decreasing glucose outflow from the liver and
(b) increasing glucose uptake in peripheral tissues, e.g. muscles and adipose tissues.
Insulin exerts these effects by interacting with the insulin receptor present on most cells. The sensitivity to insulin is a function of the number of insulin receptors of individual cells. This number is decreased or "downregulated" by insulin, i.e. high concentrations of insulin secondarily lead to relative insulin resistance. Conditions characterized by an excessive endogenous insulin secretion are obesity, type 2 diabetes, hyperlipidemia type IV of Fredricksen. In type 1 diabetes (juvenile diabetes mellitus, insulin dependent) insulin resistance is the consequence of the peripheral administration of insulin so that the glucose homeostatic function of the liver is impaired and peripheral glucose uptake excessive. The treatment of obesity, type 2 diabetes (non-insulin dependent) and hyperlipidemia consists primarly of dietary measures, i.e. caloric restriction. Patient compliance is notoriously bad and there is a need for new and better therapeutic measures. In insulin treated type 1 diabetes, hyperinsulinemia results from the fact that insulin is delivered s.c. rather than intraportally so that the delivered insulin reaches peripheral tissues first rather than after passage through the liver. There is a need to overcome the drawbacks of excessive insulin secretion and hyperinsulinemia.
Insulin-like growth factor I (IGF I) has been shown to lower blood glucose in man after intravenous bolus injection (1). Growth-promoting actions of IGF I have been documented in several metabolic conditions which have low IGF I levels in common, e.g. hypophysectomized rats (2) (5), diabetic rats (3) and Snell dwarf mice (4).
It has now been found that prolonged infusions of IGF I inhibit growth hormone secretion. In addition, blood glucose and peripheral levels of insulin remained constant but the levels of the C-peptide fell markedly indicating that endogenous insulin secretion was reduced. During IGF I infusion triglyceride, cholesterol and LDL-cholesterol tended to decrease while HDL-cholesterol increased. These findings show that during IGF I infusions insulin secretion is decreased and that IGF I helps to maintain glucose homeostasis with considerably less insulin thus overcoming the drawbacks of hyperinsulinemia. There are at least two mechanisms of action of IGF 1: As shown in the bolus experiments, IGF I leads to hypoglycemia by increasing glucose uptake primarily of muscle. It is conceivable that IGF I infusions may also facilitate glucose uptake by muscle and this effect is dose related. The second, so far unknown effect has to do with insulin degradation.
So far there exists no report on the inhibition of insulin secretion during administration of IGF I. It is foreseen that the administration of IGF I leads to a diminished need of insulin thereby preventing the secondary effects of hyperinsulinemia.


A system and method for batched, supervised, in-situ machine learning classifier retraining for malware identification and model heterogeneity. The method produces a parent classifier model in one location and providing it to one or more in-situ retraining system or systems in a different location or locations, adjudicates the class determination of the parent classifier over the plurality of the samples evaluated by the in-situ retraining system or systems, determines a minimum number of adjudicated samples required to initiate the in-situ retraining process, creates a new training and test set using samples from one or more in-situ systems, blends a feature vector representation of the in-situ training and test sets with a feature vector representation of the parent training and test sets, conducts machine learning over the blended training set, evaluates the new and parent models using the blended test set and additional unlabeled samples, and elects whether to replace the parent classifier with the retrained version.

Machine learning is a technique that uses the high speed processing power of modern computers to execute algorithms to learn predictors of behavior or characteristics of data. Machine learning techniques may execute algorithms on a set of training samples (a training set) with a known class or label, such as a set of files known to exhibit malicious or benign behaviors, to learn characteristics that will predict the behavior or characteristics of unknown things, such as whether unknown files are malicious or benign.
Many current approaches to machine learning use algorithms that require a static training set. Such machine learning approaches using algorithms that require a static training set (such as those based on decision trees) assume that all training samples are available at training time. There exists a class of supervised machine learning algorithms known as on-line or continuous learning algorithms that update the model on each new sample. However, these algorithms assume each new sample will be classified by an expert user.
A relevant machine learning method is batch mode active learning (BMAL). BMAL constructs a new classifier that is retrained based on a batch of new samples in an optionally repeatable process. BMAL, however focuses on the selection of unlabeled samples to present to the user for adjudication. BMAL conducts repeated learning until some objective performance criteria is met. Additionally, BMAL does not cover the case where the training data is split between multiple locations where original training and test data must be sent to the user where new samples are added.
Other relevant prior art methods are described in the following patents and published applications. For example, U.S. Pat. No. 6,513,025 ("the '025 patent"), entitled "Multistage Machine Learning Process," involves partitioning of training sets by time intervals and generating multiple classifiers (one for each interval). Time intervals are cyclic/periodic (fixed frequency) in the preferred embodiment. The '025 patent leverages dependability models (method for selecting which classifier model to use based on the system input) to determine which classifier to use. In addition, the classifier update and training sample addition methods in this patent are continuous. The '025 patent is also limited to telecommunications network lines.
U.S. Pre-Grant Publication No. 20150067857 ("the '857 publication") is directed towards an "In-situ Trainable Intrusion Detection System." The described system in the '857 publication is based on semi-supervised learning (uses some unlabeled samples). Learning is based on network traffic patterns (netflow or other flow metadata) not files. The '857 publication uses a Laplacian Regularized Least Squares learner and does not include a method for allowing users to select between classifiers or view analysis of performance of multiple classifiers. The '857 publication also only uses in-situ samples (samples from the client enterprise).
U.S. Pre-Grant Publication No. 20100293117 ("the '117 publication") entitled "Method and System for Facilitating Batch Mode Active Learning," discloses a method for selecting documents to include in a training set based on an estimate of the "reward" gained by including each sample in the training set (estimate of performance increase). The reward can be based on an uncertainty associated with an unlabeled document or document length. The '117 publication does not disclose detecting malicious software or files. U.S. Pre-Grant Publication No. 20120310864 ("the '864 publication"), "Adaptive Batch Mode Active Learning for Evolving a Classifier," focuses on applying this technique to image, audio, and text data (not binary files and not for the purpose of malware detection). Moreover, the '864 publication requires the definition of a stop criterion which is typically based on a predetermined desired level of performance. Importantly, the '864 publication method lacks accommodations for in-situ learning such as the potential need to provide a partial training corpus, expressing that corpus as feature vectors instead of maintaining the full sample, etc.
Existing machine learning techniques disclose learning algorithms and processes but do not cover the method for augmenting or retraining a classifier based on data not accessible to the original trainer. Existing machine learning techniques do not enable training on data samples that an end user does not wish to disclose to a 3rd-party which was originally responsible for conducting the machine learning.
Additionally, prior art malware sensors have an inherent problem in which each instance of a malware sensor (anti-virus, IDS, etc.) is identical provided their signatures or rule sets are kept up-to-date. In such instances, since each deployment of a cyber-defense sensor is identical, a bad actor or malware author may acquire the sensor and then test and alter their malware until it is not detected. This would make all such sensors vulnerable.

System and method for machine learning model determination and malware identification


Novel 3,3-diphenylpropylamines of the formula

U.S. Pat. No. 5,382,600 discloses (substituted) 3,3-diphenylpropylamines useful for treating urinary incontinence. In particular, it discloses 2-[(1R)-3-(diisopropylamino)-1-phenylpropyl)-4-methylphenol, also known as N,N-diisopropyl-3-(2-hydroxy-5-methylphenyl)-3-phenylpropylamine, with the generic name of tolterodine, as being useful to treat urinary incontinence. Tolterodine is the compound of Example 22 of U.S. Pat. No. 5,382,600.
It is preferred that tolterodine is prepared by the processes of International Publication WO98/29402 (U.S. Pat. No. 5,922,914).
U.S. Pat. No. 5,559,269 and U.S. Pat. No. 5,686,464 disclose hydroxytolterodine and related compounds as being useful to treat urinary incontinence. Hydroxytolterodine is also the major metabolite of tolterodine (Nilvebrant et al, 1997, Eur J Pharmacol, 327:195-207).
The presence of an additional hydroxyl group in tolterodine increases its hydrophilic property. In an attempt to avoid this increase, WO 99/58478 discloses substituted 3,3-diphenylpropylamines for use as pharmaceutically active substances.
The international patent application WO 98/43942 discloses therapeutically active diarylpropylamines, which have favorable anticholinergic properties, and which can be used for the treatment of disorders related to urinary incontinence.
Gillberg et al, Eur J Pharmacol 349(2-3): 285-292 (1998) have suggested that decreased potency for a muscarinic antagonist at the m3 receptor may improve the ratio of desired effects at the bladder, relative to effects on the salivary glands that result in dry mouth. Thus, a selectivity for muscarinic M3/m3 over M2/m2 receptors may result in a more pronounced effect on salivation than on bladder contraction.
It has been observed that metabolism of 3,3-diphenylpropylamines occurs in vivo. This well-known phenomenon may be involved in increased drug clearance, diminished bioavailability, diminished half-life in vivo, drug interactions, and pharmacokinetic differences between subjects, depending on their drug metabolizing enzyme activities.
Postlind et al, Drug Metabolism and Disposition, 26(4): 289-293 (1993) disclose that tolterodine is metabolized by various cytochrome P450 enzymes. The two main metabolic events are oxidation of the 5-methyl group, catalyzed by the CYP2D6 enzyme, and dealkylation of the nitrogen, catalyzed by the CYP3A enzyme.
Thus, despite the above advances in the art, it is desirable to develop novel 3,3-diphenylpropylamines that are less prone to metabolism in vivo.

This patent is subject to a terminal disclaimer.

3,3-diphenylpropylamines useful in therapy

Abstract: and stereoisomers and physiologically acceptable acid addition salt thereof; wherein R1, R2, R3, R4, R5, and R6 are as defined herein; methods of use thereof; and pharmaceutical compositions thereof.


A cover for the head of a golf club includes a heel piece and a toe piece connected by a hinge over the club bottom to swing open and closed. The hinge includes a hinge axis and arms to selectively urge the cover pieces open and closed. The cover further includes guide tabs to hold the heel and toe pieces in registry when the cover is closed, a fastener to hold the cover on a golf bag when the club is in use, and a protruding lip to facilitate a grasp to open the cover.

The subject matter of this invention is a protective golf club cover.
For a long time in the prior art, golf club covers have typically been in the form of protective mittens, either knitted or leather, which slip on and off over the club head. Such covers or mittens are sometimes tied together in a set by a tie line, in which case the line tends to get tangled among the covers and clubs. Mittens may also be used individually, i.e. not connected by tie lines, in which case they are easily lost. Until recently, covers have been used only for woods, and primarily for the aesthetic purpose of protecting the finish on the wood.
More recently, golf clubs with graphite heads have come into use. Graphite club heads, both "iron" and "woods", are subject to chipping, nicking, and such like damage from contact with each other. This damage to graphite clubs is more than aesthetic; it is substantial. It is therefore desirable to provide protective cover for both irons and woods.
A soft cover such as a mitten may provide effective and adequate protection against scratches on a wood finish, but more effective protection is required to prevent chipping and such damage to graphite clubs. Shock loading is best absorbed by a hard and stiff shield.


An aqueous ink for a transfer ink jet recording method including applying to an intermediate transfer member a reaction liquid which forms an increased viscosity ink image by coming into contact with a coloring material in the ink, applying the ink to the intermediate transfer member by an ink jet device to form an intermediate image, and bringing a printing object into contact with the intermediate transfer member to transfer the image to the object. The aqueous ink contains a coloring material which is a polymer dispersion pigment dispersed in the aqueous medium with a polymer having a hydroxyl group in its structure as a dispersant, a nonionic surfactant which is an alcohol ether surfactant a 1% aqueous solution of which has a cloud point of 33° C. or less and which has a C4-C30 alkyl group and a propyleneoxy group in its structure, and an aqueous medium.

1. Field of the Invention
The present invention relates to an aqueous ink used in transfer ink jet recording.
2. Description of the Related Art
As a printing system, is known a recording method in which an ink is ejected on an intermediate transfer member to which a reaction liquid has been applied by an ink jet recording method to form an intermediate image, and then the formed intermediate image is transferred to a recording medium to form a final image (transfer ink jet recording method). This method enables high image definition and speeding up of recording. In addition, the light fastness, water fastness and gas fastness of an image to be formed are improved by using a pigment ink.
On the other hand, when a pigment ink is used, it is known that ejection stability is improved by using a polymer having a hydroxyl group in at least a part of its structure as a dispersant (see Japanese Patent Application Laid-Open No. 2007-146128).
However, the present inventors have carried out a detailed investigation and found a problem that when a pigment ink containing, as a dispersant, such a polymer having a hydroxyl group in at least a part thereof as described above is used in a transfer recording method, deterioration of image quality may be caused in some cases due to transfer leftovers on an intermediate transfer member.


A CMOS precharge and equalization circuit for use with memory cells coupled between paired bit lines in a static random access memory array is constructed without the use of bleeder circuits. The precharge and equalization circuit is formed of a pair of precharge transistors and a pair of equalization transistors for precharging and equalizing the paired bit lines.

This invention relates generally to CMOS static random access memories and more particularly, it relates to an improved CMOS precharge and equalization circuit for use with CMOS memory cells which are coupled between differential paired bit lines.
In general, in CMOS static random access memories there are a plurality of memory cells which are arranged in an array forming columns of bits and rows of words where each memory cell is disposed for storing and retrieving binary information. Each memory cell may be comprised of a MOS cross-coupled latch (two inverters connected back-to-back) and a pair of coupling transistors coupled between the latch and a common set of interconnect lines. Since these interconnect lines are differential in nature, they are typically referred to as bit lines, which are used as a means for both writing information into the memory cell and sensing (reading) information from the memory cell via a differential read/write port.
As is well known in the art, sense amplifiers are used to detect or sense the binary state of one of the memory cells in the column of memory cells arranged between the differential bit lines. As memories become more and more dense, each of the columns is coupled with a higher number of memory cells. As a result, the pairs of bit lines become relatively long conductors which represent a relatively large capacitive load. The MOS latches are ordinarily not capable of providing a high current so as to charge up or discharge rapidly the capacitive load of the bit lines. Consequently, more time is required to charge and discharge the parasitic capacitive loads, thereby increasing write and read times to and from the memory cells.
Prior art solutions to this problem involves the provision of precharge and equalization circuits for precharging the bit lines to a particular value. As used herein, "precharge" defines the charging of a node to a specified voltage level and "equalization" defines the process of sharing charge between two nodes to insure an equal voltage level therebetween. Therefore, it can be seen that an important aspect of memory design is determining the voltage level to which the differential bit lines are precharged. The particular voltage level of the pairs of bit lines is an important consideration due to the characteristics of the memory cell and sensitivity of the sense amplifier.
In a cross-coupled pair sense amplifier, the amplifier feeds back to the bit lines. This is typically necessary to restore data in the selected memory cell. The amplifier senses small voltage differentials on the pair of bit lines and begins to further increase the voltage differential. In the usual practice, the precharge and equalization circuit is used to precharge and equalize the bit lines in a precharge cycle prior to a read cycle. That is, the differential bit lines must have null data on them. If the differential bit lines are not equalized properly, residual data on the bit lines may be transferred to the memory cell during the reading process, thereby destroying memory cell data. In such instance, the small voltage differential on the bit lines would be transferred to the memory cell and amplified therein. Thus, some form of precharge and equalization circuit is generally required for the proper operation of the memory.
In FIGS. 1a and 1b, there are shown two different prior art precharge and equalization circuits which are used to precharge or set the differential bit lines BL and BL to a predefined voltage level. The circuit 10a of FIG. 1a includes a first N-channel precharge transistor N1, a second N-channel precharge transistor N2, and an equalization P-channel P1. Ideally, the precharge voltage will be set on the respective bit lines (source electrodes of the transistors N1 and N2) at a threshold drop V.sub.Tn below the supply potential VCC or V.sub.pre =VCC-V.sub.Tn, where V.sub.Tn is a body-effect enhanced threshold. The supply potential VCC is typically at +5.0 volts, and the threshold drop V.sub.Tn varies between 0.6 and 0.9 volts. However, in actual practice the transistors N1 and N2 will tend to leak so that the voltage on the bit lines BL and BL may be charged to the full value of the supply potential VCC. In order to prevent the bit lines from charging all the way up to the supply potential VCC, a bleeder circuit 12a is usually added on each bit line so as to leak charge away from the bit lines. The bleeder circuit 12 is quite conventional and is generally formed of a polyresistor or an active device. Thus, this leakage of charge serves to insure that the precharge voltage will be maintained approximately at the VCC-V.sub.Tn level.
Similarly, the circuit 10b of FIG. 1b includes a first P-channel precharge transistor P2, a second P-channel precharge transistor P3, and an equalization N-channel transistor N3. Again, a bleeder circuit 12b is usually added on each bit line so as to prevent them from charging down to the supply potential VSS. As a result, the precharge voltage will be maintained approximately at a threshold drop V.sub.Tp above the supply potential VSS or V.sub.pre =VSS+V.sub.Tp. The supply potential VSS is typically at 0 volts, and the threshold drop varies between -0.6 and 0.9 volts.
It will be understood that in a standard random access memory array there would be additional bit line pairs or columns, each bit line in each of the columns being coupled to a bleeder circuit 12a or 12b similar to that shown in respective FIGS. 1a and 1b. For example, there may be 32 or 64 columns so as to form a 32-bit or 64-bit word. Further, each column may contain any number of bit memory cells connected between the corresponding paired bit lines. There may be perhaps 128 or 256 or more of these memory cells connected between each paired bit line so as to form 128 or 256 different words.
However, the inclusion of a bleeder circuit coupled to each bit line for all of the columns in a static random access memory array increases greatly the size of the integrated circuit and adds to the complexity of the memory. In view of this, there exists a need for an improved precharge and equalization circuit for precharging the bit lines in a static random access memory array without requiring the use of bleeder circuits. It should be noted that by eliminating of bleeder circuits there is realized a savings of power consumption. Further, the elimination of the bleeder circuits from each of the differential paired bit lines will provide reduced bit line capacitance, thereby effecting faster READ and WRITE operations.


A vehicle wheel and overlay assembly having an overlay that extends radially outward to cover substantially the entire outboard surface of the wheel, without wrapping around the periphery of the wheel. The assembly includes a wheel having a flangeless or minimum functional flange height rim flange or alternatively a truncated rim flange that terminates in a flange lip having a radially outermost edge. An overlay is attached to and closely contours the wheel outboard surface and radially terminates in a peripheral flange that has a peripheral lip with a radially outermost edge that is aligned with the outermost edge of the wheel flange lip within a predetermined circumferential margin so that the peripheral flange covers at least a portion of the wheel flange lip. This configuration gives the visible impression that this is a one-piece wheel, where the outboard surface of the overlay appears to be the outboard surface of the wheel, and not a separate component.

1. Field of the Invention
The present invention generally relates to vehicle wheels that are equipped with an attached chromium-plated wheel cover, cladding or overlay. The metal plated overlay's bond strength permits the overlay to be shaped and contoured on to the shape of the wheel, so as to maximize aesthetic effects.
2. Description of the Related Art
Automotive vehicles often include substantial amounts of metal-plated trim elements that provide both decorative and functional features. These decorative elements are widely used to enhance the aesthetic appearance of automotive wheels. In addition, an overlay not only improves the appearance of unadorned standard steel wheels, but is also used with cast aluminum wheels, which are known to be expensive and difficult to plate with chromium. Below, numerous structural approaches for combining overlays with steel and/or cast wheels are described and divided into first and second groups of prior art.
In the first group, U.S. Pat. No. 5,636,906 to Chase, owned by the assignee hereof, teaches a decorative overlay to enhance the aesthetic appearance of an automotive wheel. The overlay described in the preferred embodiment is a metal-plated plastic panel that is adhesively attached to the outboard surface of the wheel disk and may radially extend to the flange lip of a typical rim flange complying with the tire and wheel association standards so as to cover the outboard surface in the rim flange area of the wheel. The overlay provides a pleasing aesthetic effect to the wheel. The overlay covers most of the wheel's outboard surface but does not extend radially outward to cover the edge or flange lip of the standard rim flange of the wheel. The base material composition and metal plating of the overlay permit the exterior surface of the overlay to be closely contoured to the outboard surface of the wheel, namely, the disk of the wheel and a major portion or all of the standard rim flange of the wheel. Further, the overlay resists delamination of the metal plating due to heat.
A further example of a vehicle wheel having a permanently secured wheel cover is disclosed in U.S. Pat. No. 5,368,370 to Beam. Here, a chrome-plated stainless steel cladding or wheel cover includes an outer peripheral edge that is forced into engagement with the wheel within a groove formed in a typical rim flange, complying with the tire and rim association standards, along the outboard surface of the wheel. This engagement locates and holds the wheel cover in place while the adhesive cures. Since the groove is machined in the rim flange axially inboard of the edge or flange lip of the rim flange the overlay extends outward to, but does not cover the lip of the standard rim flange of the wheel. Similarly, Maloney et al., U.S. Pat. No. 5,435,631, teach a wheel cover retention system, wherein the outboard tire bead seat retaining flange or standard rim flange of the wheel includes a groove as taught in Beam for securing the wheel cover to the wheel. Again, this overlay extends outward to, but does not cover the flange lip of the standard rim flange of the wheel.
Additionally, a wheel cover that extends outward to the flange lip of the standard rim flange of a wheel was a subject of a recently issued patent owned by the assignee hereof. Chase, U.S. Pat. No. 5,564,791, teaches an overlay that extends radially outward to—but not covering—the flange lip of the rim flange of the wheel. Furthermore, this overlay is configured with the wheel to enable a standard balance weight to be secured to the rim flange of the wheel.
Finally, U.S. Pat. No. 5,842,750 to Murray et al. teaches a composite styled wheel molded in situ having a mold-formed outer edge. Murray et al. disclose a urethane foam wheel cover molded in situ and permanently affixed to the outboard surface of a wheel, wherein the urethane material extends from fastener holes in the disk of the wheel radially outwardly to cover at least a portion of an outboard standard flange edge of the wheel. Murray et al. thereby teach eliminating the prior art requirement of trimming offal formed at an outboard flange edge of the wheel in a mutli-step cutting process that results in exposing an interior cellular construction of the urethane foam.
Unfortunately, there are several problems with using a molded in situ urethane cover for a wheel. First, urethane material molded in situ directly to the outboard surface of a wheel is susceptible to degradation in quality under localized high heat applications. Urethane material will tend to break down in localized high temperatures experienced in the wheel hub area of the wheel disk under certain actual road conditions. This is particularly true in the immediate region of the wheel hub where temperatures tend to be much higher than in the outer periphery of the wheel. Further, it is understood by those skilled in the art that one reason for spacing a plastic wheel cover from the outboard wheel surface is to avoid the deleterious effects of heat generated into the disk of the wheel by the brake system, that would otherwise distort or melt the plastic wheel cover and/or delaminate any surface treatment, i.e. paint, plating, etc., applied thereto. Second, those skilled in the art also appreciate that completely filling a wheel cavity with urethane is disadvantageous in that doing so does not readily permit limiting the degree to which the urethane fills the cavity causing localized inclusions affecting wheel weight, balance and fuel economy. In other words, in situ molding a wheel cover requires a relatively large volume of expensive urethane material. Third, an additional problem associated with the manufacturing method taught by Murray et al. is that a supply of wheels must be readily and continuously available to the manufacturer for molding of the wheel cover to the wheel, rendering a manufacturing process that is somewhat complicated, expensive, and reliant upon the continuous availability of wheels, which may be impractical for just-in-time manufacturing programs. Finally, and most significantly, the plastic foamed urethane overlay taught by Murray et al. dictates a variable thickness that is wedge-shaped in cross section at the standard outboard rim flange edge of the wheel. Accordingly, the radially outermost portion of the plastic urethane overlay will be extremely thin and therefore unreliable as extremely susceptible to chipping, thereby resulting in an unacceptable surface treatment aesthetically speaking.
In each of the above prior art references, it is evident that the overlay covers only most of the outboard face of the wheel and does not reliably cover the flange lip of the rim flange at the outer extremity of the standard rim flange. Accordingly, the exposed flange lip is susceptible to damage from stone chips resulting in bare metal exposed to the ambient elements i.e. salt, mud, water, etc. Additionally, the stainless steel overlay disclosed in both Beam and Maloney et al. is highly susceptible to visible "red rust" corrosion around the periphery. This is because, at the interface where the cover is mounted in the groove in the standard rim flange, galvanic action between the stainless steel overlay and a hot roll steel wheel can result in deposits of unattractive corrosion at the interface. Further, the exposed flange lip of the standard rim flange of the wheel circumscribing the periphery of the overlay is a clear manifestation that this is a cladded wheel and tends to make the wheel look smaller. This exposure of the flange lip of the standard rim flange completely fails to meet the objective; that is, to provide a visible impression to the consumer that this is a one-piece wheel, whereby the entire visible outboard surface of the overlay appears to be the entire outboard surface of the wheel, and not a separate attachment. Wheel and wheel cover tolerances may stack up to yield noticeable eccentricity between the wheel cover and wheel. For instance, where one arcuate sector of the wheel's outboard surface at the radially outer periphery of the wheel may be adequately covered by the wheel cover, an opposite arcuate sector may be insufficiently covered, thereby yielding an obvious nonsymmetrical appearance (not chrome plated) and a wheel cover/wheel assembly that is aesthetically unacceptable. Additionally, the exposed flange lip of the standard rim flange of the wheel along the radially outer periphery of the rim flange of the overlay also tends to make the wheel look smaller and less robust to the consumer. In contrast to this first group of prior art, the second group of prior art below addresses wheel trim that extends beyond the periphery of the flange lip of the standard rim flange of the wheel.
For example, Reppert, U.S. Pat. No. 4,275,931, and Bowling, U.S. Pat. No. 4,348,061, both teach a wheel trim ring that snaps onto the standard rim flange to extend beyond the flange lip of the rim flange. Similarly, U.S. Pat. No. Re. 35,497 to Carter, III teaches a retention system for a decorative simulated wheel cover wherein the wheel cover clearly extends radially beyond an outer peripheral edge of the standard rim flange of the wheel. Additionally, Polka, U.S. Pat. No. 5,358,313, teaches an adjustable wheel liner for truck wheels wherein the cover extends well over the lip.
Todd, U.S. Pat. No. 5,143,426, teaches a standard vehicle wheel construction that eliminates the need to use an adhesive to secure a cover assembly to a wheel. Todd discloses that the cover assembly has a molded polystyrene base applied to an outboard surface of the wheel, with an ornamental thermoplastic fascia coat covering the base. The fascia coat is mechanically locked through the use of a mechanical interference with the periphery of the vent openings in the wheel to prevent separation of the wheel cover from the wheel. Todd also discloses that a peripheral edge of the fascia extends to an edge of the wheel, but does not disclose or teach any further detail for this feature. It is ambiguous from the drawings whether Todd discloses that the fascia extends to an axial edge or a radial edge of the wheel. In the perspective views of FIGS. 1 and 2, the fascia appears to extend to the axial edge of the wheel but beyond the radial edge of the wheel; whereas in the cross-sectional views of FIGS. 4a and 4b, the radial edge of the fascia appears to be in line with the radial edge of the wheel. Therefore, the disclosure of Todd is unclear as to exactly what is disclosed in regard to fascia overlap conditions with the underlying wheel's structural features.
Hodge et al., U.S. Pat. No. 5,346,288, teach a continuous cushioning member interposed laterally between a plastic wheel cover and a wheel, so as to avoid noise between the plastic cover and the steel wheel. Hodge et al. disclose that an outer peripheral portion of the cover overlies an outward turned flange portion of the wheel and is positioned in lateral proximity thereto. Like Todd, Hodge et al. does not provide sufficient disclosure with respect to the radially outer peripheral overlap of the cover to the underlying structural elements of the wheel. Because the overlapping relationships appear to be nearly co-diametrical but are nonetheless unclear, and because there is no disclosure to the contrary, it can only be reasonably presumed that the covers of Todd and Hodge et al. and the rim flanges of the wheel comply with the tire and wheel association standards.
An alternate approach to solving the problems of the first group of prior art involves not only extending the overlay beyond the radially outer periphery of the wheel, but actually wrapping the overlay around the flange lip of the standard rim flange of the wheel. For example, Beith, U.S. Pat. No. 3,726,566, teaches that the edge of the cover is formed to grip over and around the edge of the standard terminal flange of the wheel, to aid in fixing the wheel cover to the wheel. Heck et al., U.S. Pat. No. 5,595,423, and Eikhoff, U.S. Pat. No. 5,829,843, disclose similar teachings. Heck et al. disclose the use of a stainless steel overlay that covers at least a portion of the outboard facing disk of the wheel and the entire portion of the outer peripheral flange lip of the outboard bead seat retaining flange or standard rim flange. The overlay is preferably formed from stainless steel, is adhesively attached to the wheel, and has an appropriate decorative surface on its outboard side. This adhesive is applied on the outboard face of the wheel disk in a predetermined pattern, so that when the wheel cover is installed on the disk, a smearing of the adhesive occurs over substantially the entire outboard face of the disk. Since the adhesive covers substantially the entire interface between the wheel cover and the disk, it is effective to provide a seal and prevent water, mud, salt and other debris from entering between the wheel cover and the outboard surface of the wheel disk. At the outer peripheral edge of the standard rim flange facing the tire is a smooth, rounded outer peripheral end and a circumferential, radially outwardly facing groove. The peripheral end and the groove are both formed by machining operations to a predetermined specification. The groove is formed along the inboard side of the tire bead-seat retaining flange or standard rim flange. The outer peripheral end portion of the wheel cover is assembled to the smooth, rounded outer peripheral end of the wheel and terminates in the radially outwardly facing groove adjacent the rubber tire. However, this technology, like the prior art above, has several problems.
Accordingly, there is at least one unique problem with the Heck et al. '423 patent. For example, in assembling the wheel cover to the wheel, it is clear that overbend is required to accommodate the natural springback of the radial end of the stainless wheel cover. This overbend results in frictional engagement of the outer peripheral edge of the wheel cover with the smooth, rounded outer peripheral end of the wheel. This frictional engagement results in the removal of any form of protective coatings that may be on the wheel. Removal of the protective coating causes the wheel material to be in direct contact with the stainless overlay, and thereby detrimental galvanic action between the stainless steel cover and the rim flange will occur over time. There are more problems with this reference that are shared with the second group of prior art, and are described below.
The second group of prior art references address some of the concerns with the exposed flange lip of the standard rim flange existing in the first group of prior art references, but fails to address several other problems. Tire servicing, radial load deflections during operation, and "run flat" conditions are all situations in which permanent damage to the overlay or tire will occur. During tire installation and removal, service equipment that locates on the extreme periphery of the standard rim flange of the wheel will damage the prior art wheel covers that wrap around the flange lip of the rim flange. This will occur where the outermost diameter of the wheel cover is greater than that of the outermost diameter of the wheel, and could occur if the peripheral flange of the overlay is not located net against the flange lip of the standard rim flange of the wheel. Similarly, where the outside diameter of the wheel cover is greater than that of the wheel, it is likely that many wheel covers of the prior art would become damaged upon installation or removal of balance weights. Further, a larger diameter cladding is more likely to be cracked or chipped during a vehicle impact with a curb or a pothole, or as a result of material handling in the production process when outer diameters of assembled wheels collide into one another such as occurs on a gravity feed conveyor. Also, if a wheel and cladding assembly without a tire is rolled along a surface, the surface treatment of the cover (chrome plating) will chip since the cover wraps around the outside diameter of the wheel.
An additional problem with overlays which wrap around the rim flange is that the wheel and chrome plated overlay assembly appear to look larger relative to the width of the black rubber of a tire and therefore the overall aesthetics of the vehicle are affected. Wrapping the overlay around the standard rim flange of the wheel does indeed result in an overall diameter of the wheel assembly that is larger than the outer diameter of the wheel only. The only way to solve this problem is to reduce the outer diameter of the wheel before the overlay is attached to it so that when the overlay wraps around the standard rim flanges of a reduced diameter wheel the resulting assembly has the same diameter as the original design intent. Such solution is not tolerable since it affects the structural integrity of the wheel as well as significantly increases the costs of producing the wheel only.
Additionally, radial tire loads distort and deflect the standard rim flange area of the wheel during vehicle operation, as is known in the art. Because the prior art overlay actually wraps around the deflecting flange lip and standard rim flange, the deflections will in turn deflect the overlay resulting in cracking of the chromium plated surface layer. Further, these deflections of the overlay may cause the overlay's peripheral edge to become unseated from the groove or separate from the wheel. This is particularly a problem where the overlay's peripheral edge normally lies in a groove in the rim flange next to the rubber tire. There, the sharp unseated overlay edge may tear into the tire, causing severe damage.
The unseated or separated overlay poses a more likely risk under "run flat" conditions. Vehicles are sometimes run with flat tires for short distances until the tire can be serviced. Under these circumstances, the tire sidewalls distort outward over the standard rim flange of the wheel, and spin relative to the wheel. The sharp peripheral edge of an overlay wrapped around the flange lip of the standard rim flange of the wheel may tear into the rubber tire causing severe damage.
Consequently, what is needed is an overlay that covers the entire outboard surface of the wheel including a wheel where the rim flange has been reduced to a minimum functional flange height or truncated by machining and the overlay is assembled to the wheel without wrapping around the flange lip of the rim flange of the wheel so as to not affect the aesthetics of the vehicle. Such an overlay is appropriately retained with an adhesive to the outboard surface of the wheel, wherein the peripheral flange of the overlay is preferably net located against the minimum functional flange height rim flange, or alternatively against a machined wheel or truncated rim flange of the wheel. This configuration will seal the interface between the overlay and the wheel, and ensure overlay and tire integrity under all operating and service conditions of the wheel, including tire installation and removal, radial load deflections, and "run flat" conditions.

Vehicle wheel rim flange and overlay assembly


In one embodiment, a device in a mesh network joins a source-destination oriented partial directed acyclic graph (SDO-PDAG) between a source node and a destination node in the network. The device receives operations, administration and maintenance (OAM) packets flooded along reverse paths of the SDO-PDAG. The device determines, based on the received OAM packets, packet drop rate (PDR) capacities of different paths between the device and the destination node. The device replicates a data packet sent from the source node to the destination node along two or more of the paths between the device and the destination node, based on the determined PDR capacities of those paths.

Mesh networks, which typically take the form of Low power and Lossy Networks (LLNs), have a myriad of applications. For example, many sensor networks are implemented as mesh networks. Various challenges are presented with LLNs, such as lossy links, low bandwidth, battery operation, low memory and/or processing capability of a device, etc. Changing environmental conditions may also affect device communications. For example, physical obstructions (e.g., changes in the foliage density of nearby trees, the opening and closing of doors, etc.), changes in interference (e.g., from other wireless networks or devices), propagation characteristics of the media (e.g., temperature or humidity changes, etc.), and the like, also present unique challenges to LLNs.
In contrast to many traditional computer networks, LLN devices typically communicate via shared-media links. For example, LLN devices that communicate wirelessly may communicate using overlapping wireless channels (e.g., frequencies). In other cases, LLN devices may communicate with one another using shared power line communication (PLC) links. For example, in a Smart Grid deployment, an electric utility may distribute power to various physical locations. At each location may be a smart meter that communicates wirelessly and/or using the electrical power distribution line itself as a communication medium.
While Smart Grids and other sensor networks were initially designed for purposes of simply collecting data, such as meter readings, there has been recent interest in extending these forms of networks to also support automation (e.g., control loops). However, doing so would be no trivial task, as traditional mesh networks/LLNs lack the operations, administration and maintenance (OAM) signaling that is necessary to ensure the delivery of messages in a deterministic and reliable manner, while still taking into account the various constraints of the network.

Reverse operations, administration and maintenance (OAM) signaling in a mesh network


Disclosed is a power-transmitting apparatus. A power-transmitting apparatus of the present invention comprises: a pin gear provided with a plurality of pins capable of rolling movement; and a spur gear provided with a plurality of teeth and en-gagingly coupled to the pin gear so as to be relatively movable, wherein the spur gear teeth are formed with a cycloid tooth shape, and a polygonal tooth root space is formed at a tooth root region of the spur gear. As compared to a trochoid tooth shape, the tooth shape of the spur gear engagingly coupled to the pin gear so as to be relatively movable according to the present invention has a greater tooth size so that it can be applied as a cycloid tooth shape capable of maintaining a sufficient tooth contact ratio, and can resolve a reduction in tooth thickness and the wedging of the pins from an undercut at the tooth root region.

A power transmitting apparatus is largely divided into a rack and pinion for converting a rotational motion to a linear motion or vice versa and a gear train for transmitting only a rotational motion while converting a rotational speed and a torque. Typically, a power transmitting system of a power transmitting apparatus mainly uses a tooth shape according to an involute curve principle. However, there is a rare case of using a tooth shape according to a cycloid curve principle and a pin gear.
FIGS. 1 and 2 illustrate the structure of a part of a rack and pinion using an involute tooth shape according to a related art.
When a pre-load is applied to a rack and pinion using an involute tooth shape as illustrated in FIG. 1, a tooth J4 of a pinion J3 is forcibly inserted between teeth J2 of a rack J1 and contacts the teeth J2 so that a large frictional force is generated and thus efficiency is remarkably deteriorated.
Thus, at a stage of design, as illustrated in FIG. 2, a backlash that is a gap between the tooth J2 and the tooth J4 is formed to avoid a phenomenon that the tooth J4 of the pinion J3 is forcibly inserted between the teeth J2 of the rack J1.
However, when the backlash is formed as illustrated in FIG. 2, transfer or a motion is not smoothly performed, that is, a motion is transferred intermittently from the tooth J2 to the tooth J4, so that noise or vibration is generated. Further, the gears may rattle during a reverse motion.
FIG. 3 illustrates the structure of a part of a rack and pinion using a cycloid curve. FIG. 4 illustrates an undercut of FIG. 3. FIG. 5 is a structural view of FIG. 4. FIG. 6 illustrates a state in which a pre-load is applied in FIG. 3.
As a solution to solve the problem of the above-described involute tooth shape, as illustrated in FIG. 3, a rack and pinion in which a pin J5 in a roller form is used as the tooth J4 of the pinion J3 (see FIG. 1) and the teeth J2 of the rack J1 have a tooth shape formed of a cycloid curve may be taken into consideration.
According to the track and pinion of FIG. 3, since the pin J5 revolves, that is, the pin J5 performs a rolling motion, and moves on a tooth surface of the rack J1 to transfer a motion, transfer resistance is low. Further, several of the pins J5 are simultaneously engaged with several of the teeth J2 so that the motion may be continuously transferred and the rattling during reverse transfer may be prevented.
However, in the tooth J2 of the rack J1 according to the cycloid curve, when the pin J5 arrives at a tooth root J6, a radius of curvature of a central track of the pin J5 becomes zero so that, during the processing of the part of the rack J1, an undercut A such as a hatched portion in FIG. 4 may be problematic.
The undercut A may not be problematic when used for an apparatus that does not require precision. However, as illustrated in FIG. 5, it may be problematic when the undercut A is applied to an apparatus requiring high precision such as a precision mechanism because the pin J5 escapes from the tooth J2 of the rack J1 and does not follow a predetermined cycloidal track, thus failing to transfer a torque.
Further, as the escape and engagement of the pin J5 with respect to the tooth J2 of the rack J1 due to the undercut A, noise and vibration are generated so that life span of a tooth surface may be deteriorated.
In addition, as described above, in the tooth J2 of the rack J1 according to the cycloid curve in FIG. 3, when the pin J5 arrives at the tooth root J6, the radius of curvature of a central track of the pin J5 becomes zero and thus the diameter of the pin J5 matches the diameter of the tooth root J6. Accordingly, when the pin J5 arrives at the tooth root J6, about half of the outer circumference of the pin J5 closely contacts the tooth root J6 so that the pin J5 may be not rotated.
Thus, the pin J5 repeats rotation and stop at a portion around the tooth root J6 and also the pin J5 bumps against the tooth root J6 so that noise and vibration are generated. In particular, when a pre-load is applied between the rack J1 and the pinion J3 after removing backlash to improve rigidity, the above-described problem is severely generated.
As a result, in the tooth J2 of the rack J1 according to the cycloid curve, as described above, since the undercut A is generated, when the number of the pin J5 is small, a plurality of teeth J2 may not be always engaged. Also, in this area, a backlash in forward and reverse directions is inevitably generated, which has been disregarded until now.
Alternatively, a method of applying a pre-load between the rack J1 and the pinion J3 in order to remove a backlash that is a gap between the tooth J2 and the pin J5 may be taken into consideration. According to this method of applying a pre-load, since a force is applied to surfaces of the pin J5 and the tooth J2, no gap exists and initial twist of a part may be prevented so that rigidity may be greatly improved.
The tooth shape according to the cycloid curve is obtained by adding the radius of the pin J5 to a track (cycloid curve) drawn by the center of the pin J5 when the pinion J3 rolls. Thus, based on this fact, the tooth shape according to the cycloid curve has been reported as one being theoretically capable of smoothly transferring power by rolling contact.
Yet, when a pre-load is applied between the rack J1 and the pinion J3, as illustrated in FIG. 6, bump and release are made as much as the pre-load during engagement start and escape of the tooth J2 of the rack J1 and the pin J5 so that noise or vibration due to the bump and release may be generated. In particular, the bump and release causes fatigue of the pin J5 or the tooth J2 so that life span of the rack and pinion may be deteriorated.
In the above structure of the rack and pinion, to avoid the undercut of the tooth root portion and the pin and tooth forcibly insertion phenomenon that are generated when a pre-load is applied to the pin gear and the tooth gear corresponding thereto and the tooth shape of a cycloid curve of FIG. 3 is applied to the tooth shape of the tooth gear, a method of changing the tooth shape to a trochoid tooth shape may be suggested.
However, the trochoid tooth shape may have problems that reduction of a tooth size (tooth width and tooth height), reduction of a tooth shape contact rate due to reduction of a power transfer area of one tooth, remarkable deterioration of rigidity due to reduction of thickness in a tooth root portion, and shortening of life span of a pin support bearing due to an increase in a normal force applied to each pin gear during the application of the same torque due to a decrease of a pitch diameter of a pin gear by electrostatic potential.
Therefore, there is a demand for a method to solve a pin stuck phenomenon and reduction of a tooth thickness due to the undercut of a tooth root portion while a cycloid tooth shape having a tooth size higher than a trochoid tooth shape and capable of maintaining a sufficient tooth contact rate is applied to a tooth shape of a tooth gear engagingly coupled to a pin gear capable of relatively moving.