According to the present invention there is provided a spectral bio-imaging methods which can be used for automatic and/or semiautomatic spectrally resolved morphometric classification of cells, the method comprising the steps of (a) preparing a sample to be spectrally imaged, the sample including at least a portion of at least one cell; (b) viewing the sample through an optical device, the optical device being optically connected to an imaging spectrometer, the optical device and the imaging spectrometer being for obtaining a spectrum of each pixel of the sample; (c) classifying each of the pixels into classification groups according to the pixels spectra; and (d) analyzing the classification groups and thereby classifying the at least one cell into a cell class.

The present invention relates to spectral methods in general and, more particularly, to spectral imaging methods for cell classification, biological research, medical diagnostics and therapy, which methods are referred to hereinbelow as spectral bio-imaging methods. The spectral bio-imaging methods of the invention can be used to provide automatic and/or semiautomatic spectrally resolved morphometric classification (e.g., detection, grading) of neoplasm. Specifically, the methods can be used to detect the spatial organization and to qualify and quantify cellular and tissue constituents and structures associated with, for example, tumorogenesis, using, for example, light transmission microscopy combined with high spatial and spectral resolutions. Furthermore, the methods of the present invention can be used to detect cellular spatial organization and to quantify cellular and tissue natural constituents, domains and structures using light transmission, reflection, scattering and fluorescence emission strategies, with high spatial and spectral resolutions, and may therefore be employed for classification of cancer cells using what is referred herein as spectrally resolved morphometry. In particular the methods of the present invention can be used for classification of cells to developmental stages, and to qualify and quantify metabolic processes within cells. The method can further be used to develop new and more fine tuned indexes for neoplasm classification (including grading), which will eventually replace the existing indexes.
A spectrometer is an apparatus designed to accept light, to separate (disperse) it into its component wavelengths, and measure the lights spectrum, that is the intensity of the light as a function of its wavelength. An imaging spectrometer is one which collects incident light from a scene and measures the spectra of each pixel (i.e., picture element) thereof.
Spectroscopy is a well known analytical tool which has been used for decades in science and industry to characterize materials and processes based on the spectral signatures of chemical constituents. The physical basis of spectroscopy is the interaction of light with matter. Traditionally, spectroscopy is the measurement of the light intensity emitted, transmitted, scattered or reflected from a sample, as a function of wavelength, at high spectral resolution, but without any spatial information.
Spectral imaging, on the other hand, is a combination of high resolution spectroscopy and high resolution imaging (i.e., spatial information). Most of the works so far described concern either obtaining high spatial resolution information from a biological sample yet providing only limited spectral information, for example, when high spatial resolution imaging is performed with one or several discrete band-pass filters [See, Andersson-Engels el al. (1990) Proceedings of SPIE--Bioimaging and Two-Dimensional Spectroscopy, 1205, pp. 179-189], or alternatively, obtaining high spectral resolution (e.g., a full spectrum), yet limited in spatial resolution to a small number of points of the sample or averaged over the whole sample [See for example, U.S. Pat. No. 4,930,516, to Alfano et al.].
Conceptually, a spectral bio-imaging system consists of (i) a measurement system, and (ii) an analysis software. The measurement system includes all of the optics, electronics and the manner in which the sample is illuminated (e.g., light source selection), the mode of measurement (e.g., fluorescence or transmission), as well as the calibration best suited for extracting the desired results from the measurement. The analysis software includes all of the software and mathematical algorithms necessary to analyze and display important results in a meaningful way.
Spectral imaging has been used for decades in the area of remote sensing to provide important insights in the study of Earth and other planets by identifying characteristic spectral absorption features. However, the high cost, size and configuration of remote sensing spectral imaging systems (e.g., Landsat, AVIRIS) has limited their use to air and satellite-born applications [See, Maymon and Neeck (1988) Proceedings of SPIE--Recent Advances in Sensors, Radiometry and Data Processing for Remote Sensing, 924, pp. 10-22; Dozier (1988) Proceedings of SPIE--Recent Advances in Sensors, Radiometry and Data Processing for Remote Sensing, 924, pp. 23-30 ]
There are three basic types of spectral dispersion methods that might be considered for a spectral bio-imaging system: (i) spectral grating or prism, (ii) spectral filters and (iii) interferometric spectroscopy. As will be described below, the latter is best suited to implement the method of the present invention, yet as will be appreciated by one ordinarily skilled in the art, grating, prism and filters based spectral bio-imaging systems may also be found useful in some applications.
In a grating or prism (i.e., monochromator) based systems, also known as slit-type imaging spectrometers, such as for example the DILOR system: [see, Valisa et al. (September 1995) presentation at the SPIE Conference European Medical Optics Week, BiOS Europe '95, Barcelona, Spain], only one axis of a CCD (charge coupled device) array detector (the spatial axis) provides real imagery data, while a second (spectral) axis is used for sampling the intensity of the light which is dispersed by the grating or prism as function of wavelength. The system also has a slit in a first focal plane, limiting the field of view at any given time to a line of pixels. Therefore, a full image can only be obtained after scanning the grating (or prism) or the incoming beam in a direction parallel to the spectral axis of the CCD in a method known in the literature as line scanning. The inability to visualize the two-dimensional image before the whole measurement is completed, makes it impossible to choose, prior to making the measurement, a desired region of interest from within the field of view and/or to optimize the system focus, exposure time, etc. Grating and prism based spectral imagers are in use for remote sensing applications, because an airplane (or satellite) flying over the surface of the Earth provides the system with a natural line scanning mechanism.
It should be further noted that slit-type imaging spectrometers have a major disadvantage since most of the pixels of one frame are not measured at any given time, even though the fore-optics of the instrument actually collects incident light from all of them simultaneously. The result is that either a relatively large measurement time is required to obtain the necessary information with a given signal-to-noise ratio, or the signal-to-noise ratio (sensitivity) is substantially reduced for a given measurement time. Furthermore, slit-type spectral imagers require line scanning to collect the necessary information for the whole scene, which may introduce inaccuracies to the results thus obtained.
Filter based spectral dispersion methods can be further categorized into discrete filters and tunable filters. In these types of imaging spectrometers the spectral image is built by filtering the radiation for all the pixels of the scene simultaneously at a different wavelength at a time by inserting in succession narrow band filters in the optical path, or by electronically scanning the bands using acousto-optic tunable filters (AOTF) or liquid-crystal tunable filter (LCTF), see below. Similarly to the slit type imaging spectrometers equipped with a grating or prism as described above, while using filter based spectral dispersion methods, most of the radiation is rejected at any given time. In fact, the measurement of the whole image at a specific wavelength is possible because all the photons outside the instantaneous wavelength being measured are rejected and do not reach the CCD.
Tunable filters, such as AOTFs and LCTFs have no moving parts and can be tuned to any particular wavelength in the spectral range of the device in which they are implemented. One advantage of using tunable filters as a dispersion method for spectral imaging is their random wavelength access; i.e., the ability to measure the intensity of an image at a number of wavelengths, in any desired sequence without the use of filter wheels. However, AOTFs and LCTFs have the disadvantages of (i) limited spectral range (typically, .lambda..sub.max =2.lambda..sub.min) while all other radiation that falls outside of this spectral range must be blocked, (ii) temperature sensitivity, (iii) poor transmission, (iv) polarization sensitivity, and (v) in the case of AOTFs an effect of shifting the image during wavelength scanning, demanding careful and complicated registration procedures thereafter.
All these types of filter and tunable filter based systems have not been used successfully and extensively over the years in spectral imaging for any application, because of their limitations in spectral resolution, low sensitivity, and lack of easy-to-use and sophisticated software algorithms for interpretation and display of the data.
A method and apparatus for spectral analysis of images which have advantages in the above respects was disclosed in U.S. patent application Ser. No. 08/392,019 to Cabib et al., filed Feb. 21st, 1995, now U.S. Pat. No. 5,539,517, issued Jul. 23, 1996, which is incorporated by reference as if fully set forth herein, with the objective to provide a method and apparatus for spectral analysis of images which better utilizes all the information available from the collected incident light of the image to substantially decrease the required frame time and/or to substantially increase the signal-to-noise ratio, as compared to the conventional slit- or filter type imaging spectrometer and does not involve line scanning. According to this invention, there is provided a method of analyzing an optical image of a scene to determine the spectral intensity of each pixel thereof by collecting incident light from the scene; passing the light through an interferometer which outputs modulated light corresponding to a predetermined set of linear combinations of the spectral intensity of the light emitted from each pixel; focusing the light outputted from the interferometer on a detector array, scanning the optical path difference (OPD) generated in the interferometer for all pixels independently and simultaneously and processing the outputs of the detector array (the interferograms of all pixels separately) to determine the spectral intensity of each pixel thereof. This method may be practiced by utilizing various types of interferometers wherein the OPD is varied to build the interferograms by moving the entire interferometer, an element within the interferometer, or the angle of incidence of the incoming radiation. In all of these cases, when the scanner completes one scan of the interferometer, the interferograms for all pixels of the scene are completed.
Apparatuses in accordance with the above features differ from the conventional slit- and filter type imaging spectrometers by utilizing an interferometer as described above, therefore not limiting the collected energy with an aperture or slit or limiting the incoming wavelength with narrow band interference or tunable filters, thereby substantially increasing the total throughput of the system. Thus, interferometer based apparatuses better utilize all the information available from the incident light of the scene to be analyzed, thereby substantially decreasing the measuring time and/or substantially increasing the signal-to-noise ratio (i.e., sensitivity). The sensitivity advantage that interferometric spectroscopy has over the filter and grating or prism methods is known in the art as the multiplex or Fellgett advantage [see, Chamberlain (1979) The principles of interferometric spectroscopy, John Wiley and Sons, pp. 16-18and p. 263].
Consider, for example, the "whisk broom" design described in John B. Wellman (1987) Imaging Spectrometers for Terrestrial and Planetary Remote Sensing, SPIE Proceedings, Vol. 750, p. 140. Let n be the number of detectors in the linear array, m.times.m the number of pixels in a frame and T the frame time. The total time spent on each pixel in one frame summed over all the detectors of the array is nT/m.sup.2. By using the same size array and the same frame rate in a method according to the invention described in U.S. Pat. No. 5,539,517, the total time spent summed over all the detectors on a particular pixel is the same, nT/m.sup.2. However, whereas in the conventional grating or prism method the energy seen by every detector at any time is of the order of 1/n of the total, because the wavelength resolution is 1/n of the range, in a method according to the invention described in U.S. patent application Ser. No. 08/392,019 the energy is of the order of unity, because the modulating function is an oscillating function (e.g., sinusoidal (Michelson) or similar periodic function such as low finesse Airy function with Fabry-Perot) whose average over a large OPD range is 50%. Based on the standard treatment of the Fellgett advantage (or multiplex advantage) described in interferometry textbooks [for example, see, Chamberlain (1979) The principles of interferometric spectroscopy, John Wiley and Sons, pp. 16-18 and p. 263], it is possible to show that devices according to this invention have measurement signal-to-noise ratios which are improved by a factor of n.sup.0.5 in the cases of noise limitations in which the noise level is independent of signal (system or background noise limited situations) and by the square root of the ratio of the signal at a particular wavelength to the average signal in the spectral range, at wavelengths of a narrow peak in the cases the limitation is due to signal photon noise. Thus, according to the invention described in U.S. Pat. No. 5,539,517, all the required OPDs are scanned simultaneously for all the pixels of the scene in order to obtain all the information required to reconstruct the spectrum, so that the spectral information is collected simultaneously with the imaging information. This invention can be used with many different optical configurations, such as a telescope for remote sensing, a microscope for laboratory analysis, fundus cameras for retinal imaging, fiber optics and endoscopes for industrial monitoring and medical imaging, diagnosis, therapy and others.
In a continuation application (U.S. patent application Ser. No. 08/571,047 to Cabib et al., filed Dec. 12, 1995, which is incorporated by reference as if fully set forth herein) the objective is to provide spectral imaging methods for biological research, medical diagnostics and therapy, which methods can be used to detect spatial organization (i.e., distribution) and to quantify cellular and tissue natural constituents, structures, organelles and administered components such as tagging probes (e.g., fluorescent probes) and drugs using light transmission, reflection, scattering and fluorescence emission strategies, with high spatial and spectral resolutions. In U.S. patent application Ser. No. 08/571,047, the use of the spectral imaging apparatus described in U.S. Pat. No. 5,539,517 for interphase fluorescent in situ hybridization of as much as six loci specific probes (each loci located on a different chromosome) was demonstrated, as well as additional biological and medical applications.
Spectral bio-imaging systems are potentially useful in all applications in which subtle spectral differences exist between chemical constituents whose spatial distribution and organization within an image are of interest. The measurement can be carried out using virtually any optical system attached to the system described in U.S. Pat. No. 5,539,517, for example, an upright or inverted microscope, a fluorescence microscope, a macro lens, an endoscope and a fundus camera. Furthermore, any standard experimental method can be used, including light transmission (bright field and dark field), auto-fluorescence and fluorescence of administered probes, etc.
Fluorescence measurements can be made with any standard filter cube (consisting of a barrier filter, excitation filter and a dichroic mirror), or any customized filter cube for special applications, provided the emission spectra fall within the spectral range of the system sensitivity. Spectral bio-imaging can also be used in conjunction with any standard spatial filtering method such as dark field and phase contrast, and even with polarized light microscopy. The effects on spectral information when using such methods must, of course, be understood to correctly interpret the measured spectral images.
In the evaluation of infiltrating breast carcinomas, ductal and lobular carcinomas may present similar histological appearances [Azzopardi J G, Chepick O F, Hartmann W H, Jafarey N A, Lombart-Bosch A, Ozello L (1982). The World Health Organization histological typing of breast tumors. 2nd ed. Am J Clin Pathol 78:806-816]. Some quantitative histopathological variables have been identified by morphological methods as an aid to the differentiation between ductal and lobular carcinomas [Ladekarl M and Sorensen F B (1993). Quantitive histopathological variables in in situ and invasive ductal carcinoma of the breast. AMPIS 101(12):895-903]. The attempts to grade and to differentiate, or in other words to classify the tumors have been based mainly on nuclear morphology and chromatin structure [Ladekarl M and Sorensen F B (1993). Quantitive histopathological variables in in situ and invasive ductal carcinoma of the breast. AMPIS 101(12):895-903; Cornelisse C J, de Konig H R, Moolenaar A J (1984). Image and flow cytometric analysis of DNA content in breast cancer; relation to estrogen receptor content and lymph node involvement. Anal Quant Cytol Histol 4:9-18; Stenkvist B, Westman-Naeser S, Holmquist J (1978). Computerized nuclear morphology as an objective method for characterizing human cancer cell populations. Cancer Res 38:4688-4977; Dawson A E, Austin R E, Weinberg D S (1991). Nuclear grading of breast carcinoma by image analysis. Classification by multivariate and neural network analysis. Am J Clin Pathol 95:S29-S37]. Morphometric classification of other tumor types, such as but not limited to leukemias, lymphomas, sarcomas and other carcinomas [see, for example, Clarke A M, Reid W A and Jack A S (1993) Combined proliferating cell nuclear antigen and morphometric analysis in the diagnosis of cancerous lymphoid infiltrates. J. Clin. Pathol. 46:129-134] are also vastly implemented both in research medical practice.
Nevertheless, as was recently published following an NIH workshop which evaluated the reliability of histopathological diagnosis by the best pathologists in the field of cancer diagnostics, there is a discordance among expert pathologists in the diagnosis of neoplasm. Based on this workshop, it was concluded that histopathological decisionmaking is 100% subjective, regardless of the origin of specimen and that this state of affairs in histopathological diagnosis is not confined to a specific tumor, but is applicable to differential diagnosis in every organ. These conclusions were published in an editorial by A Bernard Ackerman (1996) entitled "Discordance among expert pathologists in diagnosis of melanocytic neoplasm", in Human pathology 27:1115-1116.
Close to 80% of breast carcinomas are of the ductal type [Aaltomaa S, Lipponen P: Prognostic factors in breast cancer (reviews). Int J Oncol 1:153, 1992; Toikkanen S, Jensuu H (1990). Prognostic factors and long-term survival in breast cancer in a defined urban population. APMIS 98:1005-1014]. The differentiation between ductal and lobular carcinomas has proven to be useful for evaluation of patient prognosis and determination of treatment [Ellis I O, Galea M, Broughton N, Locker A, Blaney R W and Elston C W (1992). Pathological prognostic factors in breast cancer: II Histological type; relationship with survival in a large study with long term follow-up. Histopathology 20:479-489; Eskelinen M, Lipponen P, Papinaho S, Aaltomaa S, IKosma V M, Klemi P (1992). DNA flow cytometry, nuclear morphometry, mitotic indices and steroid receptors as independent prognostic factors in female breast cancer. Int J Cancer 51:555-561; and Toikkanen S, Jensuu H (1990). Prognostic factors and long-term survival in breast cancer in a defined urban population. APMIS 98:1005-1014]. The tumors have some differences in clinical behavior and in the pattern of metastasis; lobular carcinoma is more multifocal and bilateral than ductal carcinoma [Azzopardi J G, Chepick O F, Hartmann W H, Jafarey N A, Lombart-Bosch A, Ozello L (1982). The World Health Organization histological typing of breast tumors. 2nd ed. Am J Clin Pathol 78:806-816], and patient survival expectancy is usually better [DiConstanzo D, Rosen P P, Gareen I, Franklin S, Lesser M (1990). Prognosis in infiltrating lobular carcinoma: an analysis of "classical" and variant tumors. Am J Surg Pathol 14:12-23; du Toit R S, Locker A P, Ellis I O, Elston C W, Nicholson R I, Robertson J F R (1991). An evaluation of differences in prognosis, recurrence patterns and receptor status between invasive lobular and other invasive carcinomas of the breast. Eur J Surg Oncol 17:251-257]. The two tumor types are morphologically different, cells of infiltrating lobular carcinoma are usually smaller than those of ductal carcinoma, less pleomorphic and have fewer mitotic figures. Infiltrating ductal carcinoma cells have more prominent nucleoli [Azzopardi J G, Chepick O F, Hartmann W H, Jafarey N A, Lombart-Bosch A, Ozello L (1982). The World Health Organization histological typing of breast tumors. 2nd ed. Am J Clin Pathol 78:806-816].
Some histological types of intraductal carcinoma have been recognized: comedo, cribriform, micropapillary and solid. All are recognized and classified by specific criteria and subdivided primarily by architectural pattern, cellular pleomorphism, and nuclear hyperchromasia [Page D L, Anderson T G (1987). Diagnostic histopathology of the breast. Edinburgh, Scotland: Churchill Livingstone, 120-157; Lagios M D (1990). Duct carcinoma in situ pathology and treatment. Surg Clin North Am 70:853-871; and Lennington W J, Jensen R A, Dalton L W, Page D L: Ductal carcinoma in situ of the breast: Heterogeneity of individual lesions. Cancer 73:118-124, 1994]. The survival expectancy for lobular carcinomas is usually better than that of ductal carcinomas [DiConstanzo D, Rosen P P, Gareen I, Franklin S, Lesser M (1990). Prognosis in infiltrating lobular carcinoma: an analysis of "classical" and variant tumors. Am J Surg Pathol 14:1223; du Toit R S, Locker A P, Ellis I O, Elston C W, Nicholson R I, Robertson J F R (1991). An evaluation of differences in prognosis, recurrencee patterns and receptor status between invasive lobular and other invasive carcinomas of the breast. Eur J Surg Oncol 17:251-257]. Lobular carcinomas are more often bilateral and multifocal [Ladekarl M, Sorensen F B: Prognostic, quantitive histopathologic variables in lobular carcinoma of the breast. Cancer 72:2602, 1993] and the pattern of metastasis from the tumors was found to be different. Unfortunately, histological classification of breast carcinomas is subjected to low reproducibility and attempts to classify morphological subtypes of lobular carcinomas with different prognoses, therefore seem futile [Ladekarl M, Sorensen F B: Prognostic, quantitive histopathologic variables in lobular carcinoma of the breast. Cancer 72:2602, 1993]. Both lobular and ductal types are now thought to arise from the terminal duct-lobular unit.
Characterization of nuclear features by different techniques is used for determination of diagnosis, treatment and prognosis. Quantitative estimation of various histopathological parameters such as two dimensional estimates of nuclear profile area, nuclear profile densities and mitotic profile numbers have been shown to correlate with differentiation and prognosis. Alterations in nuclear structure are the morphologic hallmark of cancer diagnosis. Nuclear size, shape, chromatin pattern have all been reported to change in breast cancer [Pienta K J, Coffey D S: Correlation of nuclear morphometry with progression of breast cancer. Nuclear Morphometry of breast cancer 2012, 1991]. However, heterogeneity in morphology and biology of tumors belonging to the same classification group has been found to be the most prominent feature of breast cancer [Komitowski D D and Janson C P (1990). Quantitive features of chromatin structure in the prognosis of breast cancer. Cancer 65:2725-2730].
Among 11 cytological parameters that were examined by de-las-Morenas et al. [de-las-Morenas A, Crespo P, Moroz K and Donnely M M (1995). Cytologic diagnosis of ductal versus lobular carcinoma of the breast. Acta Cytol 39(5):865-869] using an automated morphometric system on cytologic specimens, chromatic pattern, nuclear size and overall cell size were found to be statistically different between infiltrating lobular and infiltrating ductal carcinoma cell nuclei. Thus, the presence of coarsely granular chromatin, nuclear size of more than 44 .mu.m.sup.2 and cell size of more than 82 .mu.m.sup.2, were found to be related to ductal carcinoma.
Ladekarl and Sorensen found that the main three-dimensional nuclear size, the main nuclear profile area and the mitotic index were all significantly larger in ductal than in lobular carcinomas, whereas the main nuclear density index was smaller in ductal carcinoma [Ladekarl M, Sorensen F B: Prognostic, quantitive histopathologic variables in lobular carcinoma of the breast. Cancer 72:2602, 1993]. Yu et al. also identified some distinct nuclear features useful in the differentiation of infiltrating ductal and lobular carcinoma [Yu G H, Sneige N, Kidd L D, Johnston and Katz R L (1995). Image analysis derived morphometric differences in fine needle aspirated of ductal and lobular breast carcinoma. Anal Quant Cytol Histol 17(2):88-92].
All these methods, however, employ only image (i.e., spatial) information for analysis. A whole new dimension of analysis may be added using spectral information which reflects the interaction between light and matter. The combination of both spatial and spectral information will largely contribute to cancer detection and classification.
There is thus a widely recognized need for, and it would be highly advantageous to have, spectral bio-imaging methods and spectral morphometric methods for cells classification devoid of the above described limitations, especially the subjectiveness of pathologists in neoplasm diagnosis, which provide advanced and quantitative, semi or fully automatic, means for cancer classification.

Spectral bio-imaging methods for cell classification


An apparatus and method for providing a selectable novel reconnection algorithm for a repeater partition state machine to use in reconnecting a partitioned port. The reconnection algorithm permits selection of one of a first or a second partitioning/reconnection algorithm from a set of partitioning/reconnection algorithms. The first partitioning/reconnection algorithm corresponds to the IEEE 802.3 Standard partitioning/reconnection algorithm. The second partitioning/reconnection algorithm reconnects a partitioned port only upon minimum duration collision-free transmit activity from a partitioned port. The apparatus includes a partition state machine responsive to a counter controlled by a signal indicating the particular partitioning/reconnection algorithm selected and a device for selecting the algorithm. The signal determines whether the counter responds to receive and transmit activity or only to transmit activity. When the counter times that the minimum duration of the appropriate activity has elapsed and the partition state machine has seen activity without a collision, the port is reconnected as appropriate.

This invention relates to a method for reconnecting partitioned ports in a network. Specifically, the invention relates to a method for reconnecting partitioned ports of a repeater that is part of a network constructed with twisted pair wiring.
Repeaters conforming to IEEE 802.3 Standard, hereby expressly incorporated by reference for all purposes, partition ports that have excessive collision activity. The IEEE 802.3 Standard defines a collision as simultaneous receive and transmits activity at a single port. The IEEE 802.3 Standard also defines a port with excessive collision activity as a port that participates in each collision of a preceding set of 32 consecutive collisions. Excessive collision activity also includes a prolonged collision for a particular port.
A partition state machine partitions ports which have excessive collision activity. A partitioned port can receive transmissions, but the repeater does not relay any incoming data packets from partitioned ports. The partition state machine continues monitoring partitioned ports to determine whether it should reconnect these ports.
The IEEE 802.3 Standard defines a partitioning/reconnection algorithm which requires reconnection of a partitioned port upon collision-free transmissions or receptions relative to the port lasting a predefined minimum period. A term "port activity" defines transmission or reception at a port. Thus, the standard algorithm reconnects a partitioned port upon collision-free port activity. The IEEE 802.3 Standard sets the minimum period at or about 512 bit times.
This partitioning/reconnection algorithm may cause problems when used with repeaters that are part of a network conforming to the IEEE 10 BASE-T Standard. The 10 BASE-T Draft 10 Standard implements a network by use of twisted pair wiring, and is expressly incorporated by reference for all purposes. Networks carried out with twisted pair wiring are susceptible to installation difficulties resulting in network performance degradation due to use of inappropriate cabling. A particular port's transmit wires may not be properly terminated or the network may use untwisted wiring. In either case, transmissions from that port can produce cross-talk on the associated receive wiring of the port, thereby creating a collision. The repeater thereafter detects a collision every time the repeater tries to transmit to a node connected to such a port. The partitioning system properly partitions such a port. Unfortunately, the IEEE 802.3 Standard reconnection algorithm reconnects upon a partitioned port a minimum time duration collision-free reception at the port. The wiring problem on the transmission side of the port does not affect the reception. In this case, the partition state machine will reconnect the partitioned port after each partition, allowing later transmissions to cause collisions. This cycle degrades the performance of the network.

Selectable repeater port reconnection method and apparatus


The compounds of formula I are useful in treating gastrointestinal disorders associated with antagonizing the motilin receptor disorders. The compounds compete with erythromycin and motilin for the motilin receptor. In addition the compounds are antagonists of the contractile smooth muscle response to those ligands.

In mammals, the digestion of nutrients and the elimination of waste is controlled by the gastrointestinal system. This system is, to say the least, complicated. There are a number of natural peptides, ligands, enzymes, and receptors which play a vital role in this system and are potential targets for drug discovery. Modifying the production of, or responses to these endogenous substances can have an effect upon the physiological responses such as diarrhea, nausea, and abdominal cramping. One example of an endogenous substance which affects the gastrointestinal system is motilin.
Motilin is a peptide of 22 amino acids which is produced in the gastrointestinal system of number of species. Although the sequence of the peptide varies from species to species, there are a great deal of similarities. For example, human motilin and porcine motilin are identical; while motilin isolated from the dog and the rabbit differ by five and four amino acids respectively. Motilin induces smooth muscle contractions in the stomach tissue of dogs, rabbits, and humans as well as in the colon of rabbits. Apart from local gastrointestinal intestinal tissues, motilin and its receptors have been found in other areas. For example motilin has been found in circulating plasma, where a rise in the concentration of motilin has been associated with gastric effects which occur during fasting in dogs and human. Itoh, Z. et al. Scand. J. Gastroenterol. 11:93-110, (1976); Vantrappen, G. et al. Dig. Dis Sci 24, 497-500 (1979). In addition, when motilin was intravenously administered to humans it was found to increase gastric emptying and gut hormone release. Christofides, N. D. et al. Gastroenterology 76:903-907, 1979.
Aside from motilin itself, there are other substances which are agonists of the motilin receptor and which elicit gastrointestinal emptying. One of those agents is the antibiotic erythromycin. Even though erythromycin is a useful drug, a great number of patients are affected by the drug's gastrointestinal side effects. Studies have shown that erythromycin elicits biological responses that are comparable to motilin itself and therefore may be useful in the treatment of diseases such as chronic idiopathic intestinal pseudo-obstruction and gastroparesis. Weber, F. et al., The American Journal of Gastroenterology, 88:4, 485-90 (1993).
Although motilin and erythromycin are agonists of the mtotilin receptor, there is a need for antagonists of this receptor as well. The nausea, abdominal cramping, and diarrhea which are associated with motilin agonsits are not always welcome physiological events. The increased gut motility induced by motilin has been implicated in diseases such as Irritable Bowel Syndrome and esophageal reflux. Therefore researchers have been searching for motilin antagonists.
One such antagonist is OHM-11526. This is a peptide derived from porcine motilin which competes with both motilin and erythromycin for the motilin receptor in a number of species, including rabbits and humans. In addition, this peptide is an antagonist of the contractile smooth muscle response to both erythromycin and motilin in an in vitro rabbit model. Depoortere, I. et al., European Journal of Pharmacology, 286, 241-47, (1995). Although this substance is potent in that model (IC.sub.50 1.0 nm) it is a peptide and as such offers little hope as an oral drug since it is susceptible to the enzymes of the digestive tract. Zen Itoh, Motilin, xvi (1990). Therefore it is desirable to find other agents which are not peptides as potential motilin antagonists. The compounds of this invention are such agents.
The compounds of this invention are non-peptidyl motilin antagonists with potencies and activities comparable to known peptidyl motilin antagonists. These compounds compete with motilin and erythromycin for the motilin receptor site in vitro. In addition, these compounds suppress smooth muscle contractions induced by motilin and erythomycin with activities and potencies comparable to OHM 11526 in an in vitro model.

Cyclopentene derivatives useful as antagonists of the motilin receptor


Provided is a digital/analog converter including a voltage dividing unit that includes a plurality of voltage dividing elements and divides a reference voltage by voltage division; a first decoder that selects a plurality of voltages among the voltages divided by the voltage dividing unit; a first voltage output unit that is connected to nodes among adjacent voltage dividing elements of the voltage dividing unit and the first decoder, and outputs a plurality of voltages selected by the first decoder; a second decoder that selects any one of the plurality of voltages output from the first voltage output unit; and a second voltage output unit that is connected to the first voltage output unit and the second decoder and outputs the voltage selected by the second decoder.

1. Field of the Invention
The present invention relates to a digital/analog converter, and more particularly, to a digital/analog converter capable of controlling adjacent switching elements, of which the number is a multiple of a predetermined number, using one decoder to reduce an RC delay caused by the adjacent voltage dividing elements, thereby improving an operation speed.
2. Description of the Related Art
Digital/analog converters are devices that convert digital signals into analog signals. The digital/analog converter is generally used to convert digital data values into analog signals when a user inputs a digital control code during an image sensing process and sets up the range of digital data values that are stored according to the brightness of images.
In general, a method of using a row of resistors, a method of using capacitors, and a method of using current cells are used to divide a voltage in the digital/analog converter.
However, the known methods have a problem in that an RC delay occurs between adjacent voltage dividing elements, which results in a low operation speed.
Next, the problems of the digital/analog converter according to the related art will be described in detail with reference to the accompanying drawings.
FIG. 1 is a circuit diagram illustrating a digital/analog converter according to the related art, FIG. 2 is a diagram illustrating an RC delay of the digital/analog converter according to the related art, and FIG. 3 is a diagram illustrating a grayscale error of the digital/analog converter according to the related art.
First, as shown in FIG. 1, the digital/analog converter according to the related art includes: a voltage dividing unit 10 that includes a plurality of voltage dividing elements; a first decoder 30 that selects a plurality of voltages among the voltages divided by the voltage dividing unit 10; a first voltage output unit 20 that is connected to the voltage dividing unit 10 and the first decoder 30 and is controlled by the first decoder 30 to output a plurality of voltages divided by the voltage dividing unit 10; a second decoder 40 that selects a predetermined voltage from the plurality of voltages output from the first voltage output unit 20; and a second voltage output unit 50 that is connected to the first voltage output unit 20 and the second decoder 40 and is controlled by the second decoder 40 to output a predetermined voltage among the plurality of voltages output from the first voltage output unit 20.
The voltage dividing unit 10 includes 256 voltage dividing elements R1 to R256 connected in series to one another, and has one end supplied with a reference voltage VDD and the other end connected to the ground GND of the circuit. In addition, predetermined divided voltages are output from nodes among the voltage dividing elements R1 to R256. In this case, resistors, capacitors, or current cells may be used as the plurality of voltage dividing elements R1 to R256.
The first voltage output unit 20 includes a plurality of voltage selecting units 20a to 20p, and the voltage selecting units 20a to 20p each include 16 switching elements S1 to S16, . . . S241 to S256 that are connected to the corresponding nodes in each group of 16 voltage dividing elements among the voltage dividing elements R1 to R256 of the voltage dividing unit 10.
For example, the first voltage selecting unit 20a includes the first to sixteenth switching elements S1 to S16 that are connected to the corresponding nodes among the first to sixteenth voltage dividing elements R1 to R16, and the second voltage selecting unit 20b includes the seventeenth to thirty-second switching elements S17 to S32 that are connected to the corresponding nodes among the seventeenth to thirty-second voltage dividing elements R17 to R32. In particular, the switching elements S1 to S256 of each of the first to sixteenth voltage selecting units 20a to 20p are connected to the same output terminal of the first decoder 30 such that they are simultaneously controlled by the first decoder 30.
Further, the first decoder 30 receives a digital signal of 8 bits a0 to a7 from the outside and is controlled by four most significant bits a0 to a3 of the digital signal to select any one of the 16 voltage selecting units 20a to 20p.
That is, the first decoder 30 outputs a high-level selection signal to any one of the 16 output terminals C1 to C16 by the four most significant bits a0 to a3 of the digital signal of 8 bits a0 to a7 received from the outside, and one of the 16 voltage selecting units 20a to 20p having received the high-level selection signal outputs a divided voltage from the voltage dividing unit 10 connected thereto.
Furthermore, the second decoder 40 outputs a high-level selection signal to any one of the 16 output terminals C1 to C16 by four least significant bits a4 to a7 of the digital signal of 8 bits a0 to a7 received from the outside to select any one of the 16 voltages output from the first voltage output unit 20.
The second voltage output unit 50 includes a plurality of switching elements S1a to S16a, and each of the plurality of switching elements S1a to S16a has a gate connected to a corresponding one of the output terminals C1 to C16 of the second decoder 40 and one end connected to the first voltage output unit 20. Therefore, the switching elements S1a to S16a are turned on or off by selection signals output from the second decoder 40. When any one of the switching elements S1a to S16a is turned on by the second decoder 40, a voltage Vout is output from the second voltage output unit 50.
If the first decoder 30 outputs the high-level selection signal to the first output terminal C1 by four most significant bits of the digital signal of 8 bits a0 to a7 received from the outside, all the switching elements S1 to S16 of the first voltage selecting unit 20a having received the high-level selection signal are turned on, and the voltages divided by the first to sixteenth voltage dividing elements R1 to R16 are output.
If the second decoder 40 outputs the high-level selection signal to the second output terminal C2 by four least significant bits of the digital signal of 8 bits a0 to a7, the switching element S2a of the second voltage output unit 50 having received the high-level selection signal is turned on, and the voltage divided by the second voltage dividing element R2 among the voltages output from the first voltage selecting unit 20a is output as a final output voltage Vout.
However, in the digital/analog converter having the above-mentioned structure according to the related art, since the voltages divided by 16 adjacent voltage dividing elements among the voltage dividing elements R1 to R256 are selected by the first decoder 30 and then output by the first voltage output unit 20 at the same time, the voltages are affected by the adjacent voltage dividing elements, resulting in an RC delay.
In this case, as shown in FIG. 2, when the user wants a data waveform A, a waveform A′ is not output, but a waveform B having a time delay to reach a peak value due to the RC delay is output, which results in delay in operation.
As a result, as shown in FIG. 3, even though a voltage corresponding to Vout1 is output at a time t1, a voltage Vout2 lower than the voltage Vout1 is output at the time t1 due to the RC delay caused by 16 adjacent voltage dividing elements R1 to R16, . . . , R241 to R256, which makes it difficult to accurately represent desired brightness and color, resulting in a grayscale error.


An anchor for a floating body including a generally cylindrical outer surface, a hollow interior portion having a closed bottom surface, a top surface having an opening into the hollow interior portion, and a tubular portion extending through the cylindrical outer surface and forming; the tubular portion forming an enclosed space within the hollow interior portion; whereby in use the interior portion is receives pourable concrete through the opening in the top surface and the tubular portion receives a chain or a rope for attaching the anchor to the floating body.

Anchoring floating docks, or other floating bodies, has been an art without much improvement or change in recent times. Generally, when a dock is constructed and attached on one end to land, or otherwise fixed at one end, a further end which extends into deeper water is anchored in place. This could generally apply to pedestrian or boat docks, and includes various sizes and shapes of docks, including those that have more than one end extending into deeper water.
Typical anchors currently being used consist of weighted items or concrete forms that are tied by rope or chain to an underside of the dock and left to sink in the water on which the dock is floating. A plurality of these anchors are typically used.
One of the problems with current anchors is their overall weight. The effectiveness of an anchor is directly proportional to its weight, and thus, transporting anchors to an installation site has been a problem. This is particularly true for privately built docks, such as those at personal cottages. The typical car can only haul a very limited number of these anchors to a worksite. Even when transporting large numbers, the towing capacity of the vehicle used is crucial and the costs associated with transporting large numbers of these anchors can be prohibitive. Once transported, the anchors are also difficult to manipulate or carry by hand to particular places of use. In some cases, dock builders have resorted to using other items in large numbers to anchor the dock in place, such as a number of used tires. These impromptu solutions cause other problems, for example in the water beneath the deck.
It is therefore an object of the invention to address at least one of the aforementioned problems with the prior art, and thus provide a novel and improved dock anchor.


A charge coupled device includes shift registers, a common transfer electrode, and a floating and diffusion layer. Clock pulses are applied to the common transfer electrode. In response to the clock pulses, the common transfer electrode outputs signal charges to the floating and diffusion layer at a time when the shift registers are not being driven. Therefore, there is no output voltage level difference between the different shift registers.

1. Field of the Invention
The present invention relates to a charge coupled device (hereinafter referred to as CCD), and more particularly, to the construction of a charge-voltage converting portion thereof.
2. Description of the Prior Art
Recently, CCD shift registers are widely used for solidstate image sensing devices and analog delay devices. For these devices, a method is frequently used where a serial of information is transferred after alternately allotted and inputted into two CCD analog shift registers for the purpose of reducing a picture element pitch and a driving frequency.
Generally, an output portion of the CCD is provided with a charge-voltage converting portion, where a signal charge transferred in the CCD is converted into a voltage which is in proportion to a charge quantity thereof and is taken out as an output signal after passing through an output amplifier.
In a case where the signal charge is inputted into two CCD shift registers and transferred, it is necessary to compose these two signals thereafter. It is desirable to compose the two signals before the signal charge is transferred to the charge-voltage converting portion. If the charge-voltage converting portion and an output amplifier were provided to an output portion of each shift register, since each charge-voltage converting portion and each output amplifier sometimes have different characteristics due to the difference in manufacturing dimension, the outputs of the two CCD shift registers might be different from each other.
FIGS. 1 and 2 show the arrangement of a conventional CCD where two CCD shift registers have a common charge-voltage converting portion. FIG. 1 shows a plane configuration thereof. FIG. 2 shows timing of clock pulses and an output signal.
As shown in FIG. 1, two CCD shift registers which are an A channel and a B channel are provided in this prior art. To form these CCD shift registers, for example, n-type semiconductor areas 1 and 2 are formed on a P-type silicon substrate. On upper portions of the semiconductor areas 1 and 2, a plurality of transfer electrodes 3, 4, 5 and 6 are provided through a gate insulating film such as an SiO2 film.
In the CCD shift registers, which employ a two-phase drive method, a clock pulse .phi.1 is applied to the transfer electrodes 3 and 6, and a clock pulse .phi.2 having a phase different from that of the clock pulse .phi.1 by 180.degree. is applied to the transfer electrodes 4 and 5. A barrier for deciding a transfer direction is formed at a lower portion of each transfer electrode by ion implantation of P-type impurity. The signal charge is transferred only from the right to the left through the lower portion of the transfer electrode and is not transferred from the left to the right therethrough.
The A channel and the B channel are coupled at an output electrode 7, and connected to a floating and diffusion layer 8. The floating and diffusion layer is connected to a reset drain 10 through a reset gate electrode 9. The floating and diffusion layer 8 and the reset gate electrode 9 are formed by diffusing n-type impurity into the P-type silicon substrate at a high density. The floating and diffusion layer 8, the reset gate electrode 9 and the reset drain 10 constitute a MOS (metal oxide semiconductor) transistor. That is, the reset drain 10, the floating and diffusion layer 8 and the reset gate electrode 9 function as a drain, a source and a gate of the MOS transistor, respectively.
The potential of the floating and diffusion layer 8 is directed out to an output terminal 22 through a conductive line 11 and a MOS transistor 12. For this reason, the conductive line 11 is connected to the gate of the MOS transistor 12. The source of the MOS transistor 12 is connected to an earth terminal 23 through a resistor 13 and to the output terminal 22. In this case, the MOS transistor 12 operates as a source follower amplifier.
A DC (direct current) voltage OG is applied to the output electrode 7, while a DC voltage RD is applied to the reset drain 10. Moreover, a DC voltage OD is applied to the drain of the MOS transistor 12 through a terminal 21. Further, a clock pulse .phi.R is applied to the reset gate electrode 9.
Subsequently, the operation of the above prior art will be described with reference to FIG. 2. When the level of the clock pulse .phi.R is high at t=t1, the potential of the floating and diffusion layer 8 is RD. When the level of the clock pulse .phi.R is low at t=t2, the floating and diffusion layer 8 is under a floating condition with respect to its potential. Then, the level of the clock pulse .phi.1 is low at t=t3, the signal charge of the A channel reaches the floating and diffusion layer 8 by way of a lower portion of the output electrode 7, and reduces the potential of the floating and diffusion layer 8 by discharging the junction capacitor of the floating and diffusion layer 8. Since the quantity of the potential reduction is in proportion to the signal charge quantity, the signal charge quantity is converted into a voltage.
Then, when the level of the clock pulse .phi.R is high again at t=t4, the potential of the floating and diffusion layer 8 is RD. When the level of the clock pulse .phi.R is low at t=t5, the floating and diffusion layer 8 is under the floating condition with respect to its potential. Then, when the level of the clock pulse .phi.2 is low at t=t6, the signal charge of the B channel reaches the floating and diffusion layer 8 by way of the lower portion of the output electrode 7, and reduces the potential of the floating and diffusion layer 8 by discharging the junction capacitor of the floating and diffusion layer 8.
By repeating the above-described operation, the signal charges of the A and B channels alternately reach the floating diffusion layer 8 and are converted into voltages. The potential of the floating and diffusion layer 8 is taken out as an output signal OS from the output terminal 22 by way of the source follower amplifier consisting of the MOS transistor 12.
Japanese laid-open Patent Application H2-91954 discloses a CCD where a plurality of transfer electrodes are further provided between the end terminal and the output terminal of each channel, and clock pulses .phi.3 and .phi.4 having frequencies higher than those of the clock pulses .phi.1 and .phi.2 are applied to the transfer electrodes and thereby the signal charge is transferred to the output terminal side.
As described above, signals of the two CCD shift registers can be composed before the signal charge is transferred to the charge-voltage converting portion. Thereby, it is enabled to obtain output signals produced by the same charge-voltage converting portion and by the same output amplifier.
Even with the arrangement of FIGS. 1 and 2, however, the signal of the A channel and that of the B channel are sometimes different, particularly, in the DC level. The cause thereof is considered as follows: after the floating and diffusion layer 8 is brought into the floating condition with respect to its potential, the signal charge of the A channel reaches the floating and diffusion layer 8 by the level down of the clock pulse .phi.1, while the signal charge of the B channel reaches the floating and diffusion layer 8 by the level down of the clock pulse .phi.2.
The floating and diffusion layer 8 is capacitance-coupled with the electrodes and conductive lines to which the clock pulse .phi.1 is applied and with the electrodes and conductive lines to which the clock pulse .phi.2 is applied through an aluminum shade or a silicon substrate provided on an upper portion of the CCD through an insulating layer. Because of this arrangement, the floating and diffusion layer 8 is induced by the clock pulses .phi.1 and .phi.2. Due to the limitation in pattern layout, it is difficult to make the two capacitance couplings completely identical. Moreover, concerning the clock pulses .phi.1 and .phi.2, it is also difficult to generate them by use of clock drivers having the same characteristics. For this reason, the induction received by the floating and diffusion layer 8 is different between at t=t2 and at t=5, so that a difference is caused in the DC level.
Moreover, the above-mentioned Japanese laid-open Patent Application H2-91954 also teaches that signal charges of two channels are composed and transferred by use of a common transfer electrode. However, when the clock pulse .phi.4 of the transfer electrode is activated, since the clock pulses .phi.1 and .phi.2 of each channel are also activated, the capacitance coupling of each channel is different from each other. Thereby, the output of the signal charge of each channel is different from each other in the DC level.

Charge coupled device for overcoming an output voltage difference between different shift registers


The present disclosure discloses a method and an apparatus for processing a group chat message. The method includes: determining that a specified user is joined into a group; if at least one chat message exists in the group within a preset time period before a current time, obtaining the at least one chat message within the preset time period; selecting a chat message from the at least one chat message within the preset time period; and sending a message identifier of the selected chat message to a target server, so that the target server sends the selected chat message in the group according to the message identifier of the selected chat message. According to the present disclosure, by means of a simple selection operation, a previous chat message can be presented to a specified user that newly joins a group, thereby greatly improving processing efficiency.

With the development of communications technologies, people become increasingly dependent on instant messaging applications. In work and life, users can have a multi-person chat in the form of a group chat.
In a scenario of a group chat, a user in a group may invite other users to join the current group due to some reasons. Previous chat messages in the group are invisible to these users who newly join the group. Therefore, to enable the users who newly join the group to participate in the chat, an original user in the group may need to perform a series of operations such as screenshot capturing or copy and paste on chat message history, so as to present previous chats to the users who newly join the group. Efficiency of this processing process is quite low.
The disclosed method and system are directed to solve one or more problems set forth above and other problems.

Method and apparatus for processing group chat message

TENCENT TECHNOLOGY (SHENZHEN) COMPANY LIMITED


For the purpose of packaging diapers (10), the latter are fed to a grouping arrangement (13) in order to produce diaper groups (20, 21) from a plurality of diapers (10) positioned closely one beside the other. The diaper groups (20, 21) are fed along a plurality of conveying paths, in particular along two removal conveyors (35, 36) located one beside the other or one above the other, to a (multi-path) packaging machine or a plurality of packaging machines.

1. Technical Field
The invention relates to a method of handling planar articles, such as diapers, in particular for transporting the same and for feeding them to a packaging machine, wherein the articles, in particular diapers, coming individually one after the other from a production machine or a store, are combined into groups, in particular diaper groups, in the region of a grouping arrangement and these groups are fed to the packaging machine. The invention also relates to an apparatus for implementing the method.
2. Prior Art
Diapers are packaged as preferably folded, flat articles of in particular approximately rectangular or square shape. A respective diaper group made up of a number of abutting diapers forms the contents of a (bag) pack.
It is known to combine diaper groups by means of a compartmentalized belt (U.S. Pat. No. 5,897,291). The diapers are fed one after the other to the compartmentalized belt and are accommodated in interspaces formed between crosspieces of the compartmentalized belt. A number of diapers located one beside the other in the compartmentalized belt are pushed out, transversely to the orientation of the compartmentalized belt, by a pusher and set down as a diaper group on a platform. The latter can be moved upward and transfers the diaper group to a group conveyor which is arranged above the compartmentalized belt and transports the diaper groups one after the other to a packaging machine. This known apparatus has limited output capacity.

Method of, and apparatus for, handling nappies


Methods of optical communication and optical communication systems are described. According to a first aspect, a method of optical communication includes providing an optical signal and providing a plurality of data signals. This aspect also includes passing a plurality of desired portions of the optical signal using a plurality of respective optical modulators, the desired portions individually having at least one predefined wavelength. The method also includes optically modulating the desired portions of the optical signal using the respective optical modulators and responsive to respective ones of the data signals and outputting the desired portions of the optical signal to an optical communication medium after the modulating.

The amount of information communicated within networks, such as voice and data networks, has increased dramatically in recent years. Accordingly, such has resulted in demands for increased bandwidth in networks to communicate more information at increased rates of data transfer. As the demands for bandwidth of data communications continues to increase, improved devices and methodologies to accommodate the demands are desired.
One example of data transmission technology uses low power, high data rate and wavelength division multiplexing to achieve high bit rate data transmission. An exemplary implementation utilizes a relatively large number of optical sources at different wavelengths. However, such configurations can be relatively difficult to fabricate and relatively expensive to package.
Another solution has been to directly modulate light sources, such as laser diodes. However, the rate of modulation within such systems is less than desirable to accommodate the increasing bandwidth demands.
More specifically, conventional fiber optic communications systems typically rely on a separate source for each optical wavelength used in a wavelength division multiplexed system. However, as more and more optical wavelengths are used, larger numbers of active devices must be packaged in transmitter modules. Removing the heat from these devices constrains the package design and complicates the ability to inject high speed data signals into the devices. Also, since the optical sources are typically laser diodes, the performance of the sources varies significantly over temperature. In addition, data is encoded on each optical signal by modulation of the optical intensity at that wavelength.
Accordingly, there exists a need for an improved approach to generating frequency multiplexed optical signals.

Avago Technologies Fiber IP (Singapore) Pte. Ltd.


For a group of nickel-based superalloys, improved properties have been obtained by stabilizing at increased temperature for a reduced time relative to prior art specifications. In particular, improved creep properties have been obtained with a one-hour 1800° F. stabilization relative to a prior art four-hour 1500° F. stabilization.

The invention relates to heat treatment of superalloys. More particularly, the invention relates to stabilization of nickel-based alloys for disks and other gas turbine engine rotating parts.
The combustion, turbine, and exhaust sections of gas turbine engines are subject to extreme heating as are latter portions of the compressor section. This heating imposes substantial material constraints on components of these sections. One area of particular importance involves structural rotating parts such as blade-bearing turbine disks and shafts. The disks are subject to extreme mechanical stresses, in addition to the thermal stresses, for significant periods of time during engine operation. Shafts are subject to somewhat similar stresses and variant alloys have been developed for shaft use.
Exotic materials have been developed to address the demands of turbine disk use. Shafts are subject to somewhat similar stresses and variant alloys have been developed for shaft use. Separately, other materials have been proposed to address the demands of turbine blade use. Turbine section blades are typically cast and some blades include complex internal features.
U.S. Pat. Nos. 5,120,373 and 5,938,863 disclose advanced nickel-base superalloys. One commercial disk alloy embodiment of such an alloy has a nominal composition of 16.0Cr, 13.5Co, 4.15Mo, 4.6Ti, 2.2Al, 0.07Zr, 0.006B, 0.0025Mg, balance Ni, by weight percent. For reference, this alloy is identified as alloy "A" hereafter. A commercial shaft alloy variant has a nominal composition of 15.75Cr, 13.5Co, 4.15Mo, 4.6Ti, 2.2Al, 0.07Zr, 0.006B, 0.0025Mg, balance Ni, by weight percent. For reference, this alloy is identified as alloy "B" hereafter. Alloy "B" is a higher tensile strength alloy. Both are used in a conventionally processed (not powder metallurgical) form.
U.S. Pat. No. 6,521,175 discloses an advanced nickel-base superalloy for powder metallurgical manufacture of turbine disks. The '175 patent discloses disk alloys optimized for short-time engine cycles, with disk temperatures approaching temperatures of about 1500° F. (816° C.). Other disk alloys are disclosed in U.S. Pat. No. 5,104,614, US2004221927, EP1201777, and EP1195446.
An exemplary processing of a forging includes: solution treatment; stabilization; and age hardening stages. Exemplary solution treatment comprises heating to a high temperature effective to remove prior precipitate phases (principally gamma prime (γ′)). An exemplary temperature is in excess of 1900° F. (e.g., 1910-2015° F. in standard alloy "A" processing with an upper limit reflecting a desired control of grain size). Such a temperature is maintained for an interval effective to achieve desired precipitate phase removal (e.g., two hours in standard (prior art) alloy "A" processing). Air cooling or a faster cooling rate is then performed to rapidly decrease temperature to avoid precipitate formation at undesirable intermediate temperatures. An exemplary cooling is to a temperature near or below 1000° F.
Stabilization serves to form carbides at grain boundaries. Exemplary stabilization comprises heating at an intermediate temperature effective to form sufficient carbides to stabilize the grain boundaries (e.g., 1500+/−25° F. in standard alloy "A" processing). Such a temperature is maintained for an interval effective to achieve the desired carbide formation (e.g., four hours in standard alloy "A" processing). Fan air cooling or an equivalent is then performed to similarly avoid any precipitate formation at undesirable intermediate temperatures. An exemplary cooling is to a temperature near or below 1000° F.
Age hardening (precipitation heat treatment) serves to grow desired γ′ within the γ matrix. Exemplary age hardening comprises heating at a lower temperature and for a time effective to grow a desired size and volume fraction of γ′ (e.g., 1350+/−25° F. for eight hours in standard alloy "A" processing). Air cooling or fan air cooling is then performed to rapidly terminate γ′ formation.


The flow rate of molten aluminum through a trough is measured by damming off the trough and diverting the flow through the measuring tube of a magnetic flow meter having a diameter, and located at a level in the trough to create a head of molten aluminum sufficient to produce a flow through the tube which is within the operating range of the meter. The apparatus includes a pair of spaced apart dam members forming a cavity therebetween which is transversed by the measuring tube. The magnet of the flow meter is located in the cavity preferably in a housing through which cooling air is circulated. The electrodes are made of an electrically conductive material which is resistant to corrosion by the molten aluminum, preferably, titanium diboride. Spring biased tapered connections seal the measuring tube with the dam members which have peripheral seals to keep molten aluminum out of the cavity.

1. Field of the Invention
This invention relates to the measurement of the flow of molten aluminum, and in particular, the flow of molten aluminum through a trough using a magnetic flow meter.
2. Background Information
Magnetic flow meters for measuring the flow rate of electrically conductive liquids are well known. They operate on the principle that a conductive liquid flowing through a magnetic field applied at right angles to the direction of flow generates an electromotive force or voltage. This voltage is proportional to the velocity of the conductive liquid. By knowing the cross-sectional area of the flow, the volumetric flow rate is easily calculated.
Magnetic flow meters have some very desirable characteristics. First, the design is very simple; there are no moving parts. There also are no internal impediments to flow, they can operate in high temperature environments, they are versatile in that they can be installed in any desired location or position, they have a broad measurement span, they can measure bidirectional flow, they are unaffected by variations in viscosity, pressure, temperature and density of the media, and they have an accuracy of at least better than plus or minus 2%.
Magnetic flow meters have been successfully employed in industry for over two decades for monitoring flow control of molten sodium in nuclear reactors and for the measurement of the flow rates of molten brass, lead and a variety of other fluids with the only criteria for implementation being that the media be electrically conductive.
However, applicants are aware of no successful application of a magnetic flow meter to measuring the flow of molten aluminum, which presents special problems. First, the temperature of the molten aluminum is high, typically about 1350.degree. F. Also, molten aluminum is highly reactive. Not only must the components which contain the molten aluminum be resistant to corrosion, but even more importantly, the electrodes of the magnetic flow meter must be capable of operating with hot molten aluminum for prolonged periods of time without eroding, fouling or changing their electrical characteristics.
U.S. Pat. No. 4,741,216 proposes either lining or constructing the measuring tube of a magnetic flow meter through which molten aluminum passes with silica carbide to resist corrosion. However, this patent also suggests using wire electrodes without specifying any particular material. Common high temperature electrode materials like steel wire are rapidly dissolved by molten aluminum. But even slow erosion causes drifting of the meter as the voltage generated by the meter is directly proportional to the distance between the electrodes. Erosion or fouling changes this critical distance.
U.S. Pat. Nos. 4,507,975 and 4,716,649 disclose a magnetic flow meter for measuring the flow rate of the liquid sodium, for instance, in a nuclear reactor, and uses platinum or platinum alloys for the electrodes. Such materials are dissolved by molten aluminum.
Molten aluminum is also very difficult to contain. It can leak through any crack or crevice through which water can pass. This property of molten aluminum, considered in addition to its high temperature and reactivity, make it very difficult to select materials and effect seals.
Because of the difficulty in containing molten aluminum, it is usually conveyed in open troughs rather than enclosed pipes. In the typical production process, flow rates of a molten aluminum are not measured, but obtained indirectly by some other measurable quantity or variable of the process such as pumping speed, changes in metal height, mass flow by temperature balance calculation and casting rates. None of these approaches provide an accurate, real time indication of flow rates of the molten metal. In addition, the accuracy of each measurement is restricted to the techniques used to obtain the values of the described process parameters. At present, no direct reading operational flow meter system exists for molten aluminum flow measurement.
Accordingly, it is a primary object of the invention to provide on-line, real time magnetic flow meter measurement of molten aluminum flow rates and in particular, measurement of molten aluminum flow rates through a trough.

Apparatus and method for measuring flow rate of molten aluminum through a trough


Disclosed is a nonvolatile cache memory including a nonvolatile memory part and a cache controller. The nonvolatile memory part is configured to store cache data. The cache controller is configured to control reading and writing of the cache data with respect to the nonvolatile memory part. Further, the cache controller is configured to perform, as a preparation for an interruption of power supply, standby preparation processing to generate standby state data and store the generated standby state data in the nonvolatile memory part. Further, the cache controller is configured to perform, at resumption of the power supply, restoration processing of the cache data stored in the nonvolatile memory part using the standby state data.

The present disclosure relates to a nonvolatile cache memory, a processing method of the nonvolatile cache memory, and a computer system having the nonvolatile cache memory.
In a known computer system, a processor acquires data and information such as a command from a main memory or updates the information of the main memory. At this time, accessing performance such as the latency of the main memory is inferior to the processing performance of the processor. Therefore, a difference in the performance between the main memory and the processor causes a bottleneck to the total performance of the computer system.
A cache memory is a memory newly provided in a storage layer to eliminate the bottleneck and arranged between the processor and the main memory.
In general, a SRAM (Static Random Access Memory) that operates at higher speed than the main memory is used as the cache memory.
When the processor acquires the data from the main memory or updates the information of the main memory, the same data is also stored in the cache memory. Next, when the same data is acquired or updated, the high-speed cache memory performs the input and output of the data instead of the main memory. Thus, the difference in the performance between the main memory and the processor is covered up, whereby the high-speed computer system is constructed.
Meanwhile, in order to apply a computer system to mobile equipment, there is an increasing demand for a power saving control technology. In a semiconductor circuit technology used in the latest high performance processor, a ratio of a leakage current to power consumption is large. Therefore, there has been used a technology so-called power gating to interrupt power supply to a processor to prevent a leakage current from occurring, for example, when there is no command to be processed.
On the other hand, a SRAM used as a cache memory is a volatile memory. Therefore, data stored in the SRAM is lost as the power supply is interrupted. In view of the problem, Japanese Patent Application Laid-open No. 2011-150653 discloses a method of interrupting power supply only to a controller that controls the input and output of data while retaining the power supply to a SRAM cell array that stores the data among parts constituting a cache memory to reduce power consumed in the cache memory.

Nonvolatile cache memory, processing method of nonvolatile cache memory, and computer system


A method of working paperboard blanks is disclosed. The method includes providing first and second pairs of parallel rotary shafts supporting first and second pairs of tool heads respectively. The first pair of tool heads is moved to a predetermined longitudinal position along the first pair of shafts to define a first line of working. Likewise, the second pair of tool heads is moved to a predetermined longitudinal position along the second pair of shafts to define a second line of working wherein a center of the first line of working is displaced relative to a center of the second line of working. The paperboard blank is conveyed between the first and second pairs of tool heads to form a panel line on the paperboard blank. The tool heads may be automatically positioned along their respective shafts by coupling members which move linearly parallel to the shafts.

1. Field of the Invention
The present invention relates to a method of working paperboard blanks and, more particularly, to a method of offsetting tool heads to form a panel line on a paperboard blank.
2. Related Prior Art
Boxes, such as those made from corrugated board or paperboard, are generally made by cutting a paperboard blank to the desired outside dimensions of the various walls and flaps, scoring the blank to form a crease line where the box is to be folded and slotting the blank to form the various flaps of the box. The crease lines and slotting lines are often referred to as "lines of working" on the paperboard blank. In conventional machines for forming box blanks, the tool heads for slotting and scoring the blanks are mounted in mating positions on successive pairs of shafts wherein each pair of shafts is oriented with one shaft above the other. Thus, the slotting and scoring operations take place serially as the blank is fed along a horizontal feed path into a nip as defined by blades or profiles on each set of mating tool heads on paired shafts.
Accurate scoring is critical to the squareness and joint gap control of the resulting box. The crease line formed by scoring must be wide enough to allow a fold to occur without rolling and thereby creating a false fold line. Further, the crease line should not be so narrow as to create cracking of the inside liner of the corrugated board, thereby weakening the box. However, a crease line which is too wide will lack adequate strength as it will tend to roll. The proper width of the crease line depends upon the thickness or caliper of the paperboard blank. For light weight papers and thin blank calipers, only a narrow crease line is required. However, to ensure proper box folding, heavy weight papers and thick blank calipers require a wider crease.
In the prior art methods associated with typical box forming machines, each crease line is formed by a series of mating scoring heads aligned in the direction of board travel wherein the successive scoring profiles share a common center axis. This prior art process is often referred to as an in-line arrangement of scoring heads. Each successive downstream set of mating scoring heads produces a score line superposed over the preceding score line such that each score line shares a common longitudinal axis resulting in a crease line centered on such axis.
In order to change the width of the resulting crease line in this prior art process, each set of mating scoring heads along the common longitudinal axis is replaced with another set of heads having scoring profiles of a different width. A plurality of scoring heads having different width profiles are typically located along each supporting shaft. When crease lines of a different width are desired, the scoring heads must be manually repositioned along their respective shafts such that the scoring profiles of desired width are aligned for engaging the corrugated board. Further, attempts to produce crease lines of varying widths in a conventional in-line arrangement of scoring heads has often resulted in increased crushing pressures and cracking, especially when light weight liners or thin board calipers are used.
In response to the limitations of traditional scoring or creasing methods, "dual" or "progressive" scoring has been proposed wherein crease lines are formed by a primary pair of mating scoring heads followed by a secondary pair of mating scoring heads, each pair having scoring profiles of a different shape to ensure a well defined crease line. However, progressive scoring utilizes a traditional in-line arrangement of scoring profiles in that the profiles of both the primary scoring heads and secondary scoring heads share a common center axis thereby requiring the replacement of scoring heads when a change in crease line width is desired.
In addition to forming crease lines of desired width, conventional methods of working paperboard blanks include forming slotting lines by passing the blank between mating slotting heads. Each slotting line is usually associated with a crease line to define a single panel line wherein the slotting line typically shares a common longitudinal axis with the crease line. It is sometimes desirable, however, to offset the slotting line from its associated crease line such that the flaps of the resulting box may be folded in a particular configuration. When such offsetting is desired, the prior art methods require that the slotting and scoring heads be manually repositioned along their respective shafts such that the center axes of the slotting and scoring lines are spaced apart by the desired offset.
This manual repositioning of tool heads has proven to be a time consuming task resulting in decreased production efficiency. Typically, the machine operator must physically enter the working area of the machine to manually disengage the tool heads from their respective shafts and then push the tool heads to their new positions.
Accordingly, there is a need for a method of scoring paperboard blanks to form a crease line wherein the width of the crease line may be easily varied without requiring the replacement of the scoring tool heads. In addition, there is a need for such a method for producing a well-defined crease line without cracking the paperboard blank. Further, there is a need for a method of displacing tool heads to form offset lines of working on a paperboard blank without requiring the manual repositioning of the tool heads.


This invention relates to an electronic element having an electron function which acts even at room temperature using a super dielectric effect. The element has a crystalline electron system, and uses a perovskite crystal in the ground state of a “macroscopic quantum effect” which occurs when the electron number is defined, or nearly defined. The electronic element used in an electric field such that the two-dimensional plane of doped crystals ground state of a “fractional quantum Hall effect” wherein the doping amount of the crystals is 0.05 or less, or if localization is introduced, 0.6 or less, and the crystals may have a doping amount variation determined by the degree of localization.

A "Johnson element", which is an example of an electronic element using a "macroscopic quantum effect" wherein two superconductors are joined together via a thin insulating barrier, is known in the art. In this element, the junction current which is a function of the magnetic flux, periodically varies with a unit flux quantum of Φ0 according to I=V0 sin(2πQ/Q0). Using this element, an electronic circuit can be constructed having one flux quantum of Φ0=2×10−15 [Wb] as an information unit.
However, as this element uses a superconductor, a low temperature environment such as liquid helium temperature or liquid nitrogen temperature is required, and as it has an operational limiting frequency of 1 THz, it is not much faster than a semiconductor element.
A "single electron tunnel element" is also known which does not use the macroscopic quantum effect, wherein, by giving the element a small electrostatic capacitance, the movement of other electrons is suppressed by the increase of Coulomb energy produced by the movement of one electronic charge (e=1.6×10−19 [C]), one electronic charge being used as one information unit. It is considered that, for an element having dimensions of approximately 100 nanometers, a low temperature environment such as that of liquid helium is required for stable operation. To permit stable operation at room temperature, the element dimensions must be reduced to several nanometers or less in order to reduce electrostatic capacitance. In addition, the usual electrodes and wires cannot be attached, and as it has an operational limiting frequency of about 1GHz, its performance is also inferior to that of a semiconductor element.
Problems Which this Invention Aims to Solve
Hence, the electronic element using the "macroscopic quantum effect" or the single electron tunnel element of the related art require a low temperature environment, and an electronic element using the "macroscopic quantum effect" which operates at room temperature was desired.
Means to Solve the Above Problems
This invention is an electronic element used in an electric field such that the two-dimensional plane of doped crystals forming the electronic element is effectively perpendicular to the electric field, and which can be used at room temperature. The element is in a ground state wherein the "fractional quantum Hall effect" is stable. The doping amount of the crystals is 0.05 or less, or if localization is introduced, 0.6 or less, and the crystals may have a doping amount variation determined by the degree of localization.
The thickness of the electronic element may be effectively n/2 (n is an integer equal to one or more) times the plasma oscillation wavelength of the electrons in the crystal.

Electronic element operable at room temperature using super-dielectric phenomenon


Improvements to a manually operated, rotary bristle toothbrush. A thumb actuated mechanism is slidably and longitudinally mounted in an essentially hollow, elongate handle and a part of the mechanism, a rack, is caused to engage at least one compound pinion/spur gear in order to convert longitudinally reciprocative motion to rotary motion that is shunted toward the head of the toothbrush. The head contains therein one or more rotary bristles that project orthogonally from the head of the toothbrush and off the major longitudinal axis of the device. Rotary motion is conducted by a drive shaft into the head of the brush and transferred via a crown gear to bases of the brush(es) by interface between the crown gear of the drive shaft and at least one brush base comprising a capstan device adapted for rotation.

1. Field of the Invention
This invention relates generally to manually driven brushes and, specifically, to improvements in manually driven, rotary brush toothbrushes or similar apparatus.
2. Discussion of the Relevant Art
Over the past three decades, dental prophylaxis, in the form of regular brushing with decay-preventing dentifrices, has served to improve the nation's dental and general health to a significant degree. Notwithstanding the advances in dentifrices, there has been little improvement in the toothbrush used by the vast majority of persons practicing dental hygiene on a two- or three-time a day basis. That is not to say that changes in bristle quality, shape of the brush and/or size of the toothbrush article have not been improvements; but to the average toothbrush user, parametric changes to the conventional, straight handled "scrubbing" toothbrush comprise the preponderance of improvements to the original. Of course, there have been marketed numerous toothbrushes wherein the bristles or brushes of the apparatus move reciprocatively in lateral or longitudinal translation, and even those which possess rotary bristles or brushes. But, almost all of the truly successful products are motor driven. Short of returning to the pristine handbrush, there is a paucity of manually driven toothbrushes in which the bristles are caused to translate or rotate after the fashion of the many power driven brushes, as discussed above.
In making the instant invention, I performed a diligent search, not only on the market shelves and in catalogues, but in the records of the United States Patent and Trademark Office as well. Several patents were located, in the latter search effort, in which various patentees improved both power driven and manually operated toothbrushes in order to acquire certain characteristics and/or achieve specific goals. In the former category, power driven brushes, U.S. Pat. No. 4,079,517 issued to Zacharia discloses an electrically driven brush having an extension shaft from the end of which projects an orthogonally disposed rotary brush. Because the brush is electrically powered, Zacharia is particularly concerned with providing water tight seals in the power unit-extension shaft region and at the power unit-rotating shaft interface portion of the unit. A disadvantage of the '517 device is that, even were it not to require (as it does in this case) a transformer unit, the entire ensemble remains both bulky and relatively heavy; and it does not appear to be the type of device which one will readily carry to work and employ regularly away from the home or in the workplace. Although having the advantage of applying uniform force to the teeth and all areas of the mouth, the disadvantages, combined with the cost of production, make this device generally undesirable for usage away from the home. Only a manually operated (driven) and inexpensive device will overcome these disadvantages. In 1981, a power driven brush assembly was patented by Cohen, U.S. Pat. No. 4,274,173, and employed a triple rotary brush ensemble in the cleaning head. The triple rotary brushes are belt driven and therefore move unidirectionally. The main thrust of the '173 teaching appears to be in the cup-shaped cavities located in a free end of each individual brush. Further, the captured brush end appears to be removable from a rotary base which comprises a spur gear. The spur gear bases, however, are toothed in order to engage a drive belt and do not enmesh with each other. Further, a drive pin is used to fixedly secure the brush end in the spur gear base. In addition to having disadvantages which I have cited regarding the '517 device, the '173 employs a drive belt which, if broken, is not easily replaceable by the user. Further, although the patentee means to say that adjacent brush surfaces rotate in opposite directions, the brushes, nonetheless, rotate in the same direction. My studies have convinced me that there is no particular merit to this type of brush movement and, further, obtainment of such is usually at a cost of greater complexity than is either necessary or desired in the multiple brush ensemble. I prefer, as the reader will hereinafter see, to employ a plurality of contrarotating brushes because the scrubbing action is not diminished and the mechanization required for obtaining this function is less costly and far less contrived.
Final to my search of the patent records, a rotary toothbrush disclosed in U.S. Pat. No. 1,949,241, issued to Carlson et al., although encumbered by a thumb actuated rack and drive pinion design, is nonetheless noteworthy for its early genesis and unusual brush shape. Patent '241 employs a transversely mounted, thumb actuated, spring biased rack-on-plunger to engage a pinion gear compounded with a crown/spur gear. The crown gear (of the spur) engages a pinion mounted at the end of a drive shaft. At the other end of the drive shaft is a removably mounted helical brush. The thumb actuated, transversely mounted drive rack plunger has an inherently serious disadvantage. When the '241 brush is held in the hand and the thumb placed on the plunger and actuated to reciprocatively move the rack in a direction transverse the longitudinal axis of the brush, a force coexists which not only serves to rotate the helical brush but also causes a forcing of the brush head end away from the user's teeth. As the spring biased rack/plunger is rebiased, a natural tendency for the user would be to repress the brush onto the surface of the teeth. Thus, in the sporadic pumping action required to actuate the brush, the user inadvertently applies an irregular pressure, almost periodically, to the teeth. Because the thumb actuated rack is subject to a rebiasing mode, a strong deceleration is applied to the brush surface by contact with the teeth and the effects of the rebiasing mechanism then tend to be overridden. To correct this deficiency, a heavier rebiasing spring would only cause the user to apply more pressure to the thumb actuated rack-plunger and thus a greater force when "pushing" the brush off the teeth as (previously) mentioned. It would appear that in '241, actuation transverse the longitudinal axis of the brush is ill-advised in my judgement.
In order to provide a truly functional, portable and manually operable rotary brush device, improvements had to be directed toward certain disadvantages of the current art as well as those factors which encourage regular use of a mechanical contrivance in favor of the more conventional static toothbrushes of the genre.