In performing harmonic echo imaging, the necessity of changing modes is obviated, maneuverability is improved, and diagnostic information of the kinetics of a blood flow is provided with high reliability. A diagnostic ultrasound system provides, by scanning a cross section of an object with an ultrasonic beam signal, a normal B-mode image (the first tomographic image) of a tissue and a harmonic-mode image (the second tomographic image) of distribution information of an ultrasonic contrast medium injected into the object. The distribution information is obtained based on a non-fundamental frequency component (e.g., second harmonics) other than a fundamental frequency component of the ultrasonic beam signal. The system comprises a unit for scanning an ultrasonic beam signal along the cross section to acquire an echo. The scanning unit controls the scan so that the beam signal is scanned automatically and alternately for each raster in both the normal B-mode and the harmonic-mode. Preferably, the scan in the harmonic-mode precedes that of the normal B-mode. Image data of the first and second tomographic images are visualized on the basis of the echo.

1. Field of the Invention
The present invention relates to a diagnostic ultrasound system, or more particularly, to a diagnostic ultrasound system having the ability to implement an imaging method referred to as "harmonic echo imaging" in which ultrasonic waves are scanned with an ultrasonic contrast medium injected into a patient body for the purpose of detection and quantitative assessment of perfusion of blood through a tissue.
2. Description of the Related Art
A diagnostic ultrasound system for producing an image signal through transmission and reception of ultrasonic waves has been employed in various ways owing to the noninvasiveness of ultrasonic waves in the past. Conventional diagnostic ultrasound systems produce tomographic images of a soft tissue of a living body by adopting ultrasonic pulse reflection imaging. This imaging method is noninvasive and produces a tomographic image of the tissue. Compared with other medical modalities such as diagnostic X-ray imaging, X-ray CT imaging, MRI, and diagnostic nuclear medicine imaging, the imaging method has many advantages: real-time display is possible, a compact and relatively inexpensive system can be constructed, patient exposure to X- rays or the like will not occur, and blood flow imaging is possible owing to ultrasonic Doppler imaging. The imaging method is therefore most suitable for diagnosis of the heart, abdomen, mammary gland, and urinary organs, and for diagnosis in obstetrics and gynecology. In particular, pulsation of the heart or motion of a fetus can be observed in real time through simple manipulation that is as simple as placing an ultrasonic probe on a patient's skin. Moreover, since patient exposure need not be cared about, screening can be carried out many times repeatedly. Furthermore, there is an advantage that a system can be moved to a bedside position for ready screening.
Under these circumstances, a new screening method for screening the heart or abdominal organs using ultrasonic waves has been developed in recent years. The method is such that ultrasonic waves are scanned with an ultrasonic contrast medium injected trans-venously, and a resultant image is used to evaluate the kinetics of a blood flow (Refer to, for example, U.S. Pat. No. 5,410,516 or Published Japanese Translation of PCT International Publication for Patent Application No. 4-501518. Since trans-venous injection of a contrast medium is less invasive than trans-arterial injection, the method for evaluating the kinetics of a blood flow is becoming popular. As an ultrasonic contrast medium, for example, a "5%-diluted human albumin with bubbles produced manually or using a sonicator" is known. The main component of the contrast medium is microscopic bubbles that act as a source of reflect ultrasonic waves. The larger the amount and concentration of injected contrast medium is, the larger the effect of contrast imaging is. However, since the bubbles are crushed due irradiation of ultrasonic waves, the time during which the effect of contrast imaging persists is shortened. Although a contrast medium characteristic of high persistency and high durability against sound pressure has been developed in recent years, the long-term persistence of the contrast medium in a human body predictably raises invasiveness.
A technique for detecting the presence or absence of blood flow in a diagnostic region by checking if luminance is intensified by a contrast medium has been adopted for the most fundamental diagnosis using an ultrasonic contrast medium. For more advanced diagnosis, a technique for acquiring information of a temporal change in spatial distribution of a contrast medium in a diagnostic region by detecting the spread of a change in luminance or the extent of intensification of luminance has been adopted. Also employed is a technique for obtaining information of a temporal change in spatial distribution by measuring a time required for an injected contrast medium to reach a region of interest (ROI) and a temporal change in luminance of echoes deriving from a contrast medium in a region of interest (time density curve (TDC)) or a maximum luminance. Processing of detecting a change in the level of ultrasonic echoes from a contrast medium which is necessary for those techniques is conventionally such that a change in the level of luminance of a B-mode image is checked merely visually, or image data of a plurality of frames are stored temporarily in a memory and then read in order to plot a histogram and thus quantitatively measure a change in level of echoes or plot a TDC.
In recent years, "harmonic echo imaging" has been devised as a technique for improving the effect of intensifying contrast echoes affected by an ultrasonic contrast medium. The harmonic echo imaging is based on the fact that microscopic bubbles of a contrast medium facilitate occurrence of an acoustic nonlinear phenomenon, that is, generation of reflected waves or echoes of nonlinear components or especially harmonics which are components other than the fundamental components of transmitted waves, and intended to distinguish in level echoes of harmonics from echoes emanating from an organ in a body that hardly generates harmonics. For example, reflected waves or echoes include fundamental components of transmitted waves and harmonics thereof stemming from a contrast medium. By displaying echoes remaining after the fundamental components are removed by a filter, the harmonics. That is, an image reflecting the extent of intensification due to the contrast medium can be obtained.
As mentioned above, using the harmonic echo imaging, once a relatively small amount of contract medium is administered, the presence or absence of the contrast medium in a region of interest, that is, the perfusion of blood, can be observed, and information helpful in diagnosis can be acquired.
However, for diagnosis based on harmonic echo imaging, when mere visualization based on the harmonic echo imaging is carried out, various drawbacks described below arise.
First, there is a problem concerning a diagnostic mode. Before administration (injection) of an ultrasonic contrast medium, a nonlinear effect exerted by an organ, vessel, or blood in the body is limited. Even if harmonic echo imaging (harmonic mode) is carried out in this state, almost no image information can be acquired. Therefore, when a region of interest is searched for and defined prior to administration of a contrast medium, the harmonic mode must be changed to a B-mode (normal B-mode) designed for interpreting a normal gray-scale tomographic image. Manipulation becomes time-consuming because of this mode change.
Secondly, there is a problem concerning the specification of a region to be observed. Assume that an ultrasonic contrast medium is administered and the magnitude of dying and shadowing by the contrast medium is observed. Since the effect of dying and shadowing decays gradually, the contour of an organ may not be observable. In this case, if a region to be observed becomes inconsistent with an object organ of observation on a tomographic image by accident, an observer may not be aware of the fact. Since this kind of accident is predicted, the results of diagnosis are naturally accompanied with a concern about reliability.
Thirdly, there is a problem attributable to microscopic bubbles that are the main component of an ultrasonic contrast medium. It is known that the microscopic bubbles are very delicate and vanish with irradiation of specific ultrasonic waves. As for this matter, sound pressure in the presence of ultrasonic waves capable of demolishing bubbles has been reported in, for example, a thesis entitled "In vitro detection of cavitation induced by a diagnostic ultrasound system" written by Christy K. Holland et al. (IEEE Trans. on Ultrason. Ferroelec. and Freq. Cont., Vol. 39, No. 1, January 1992). This report was verified by an experiment conducted by the present inventor. It has been confirmed that the sound pressure of a level usable in clinical practice may cause collapse of bubbles.
Furthermore, it is known that bubbles have a frequency characteristic dependent on the size (diameter) of an incident ultrasonic beam in the presence of which a sound pressure is detected. In particular, at a resonant frequency, bubbles vibrate with a large amplitude and eventually collapse or cavitate. If vanishing of bubbles due to irradiation of ultrasonic waves occurs at a rate that is higher than the speed of supplying a contrast medium (microscopic foams), echoes intensified by the contrast medium cannot be acquired. Consequently, proper values of physical quantities serving as conditions for transmission such as the sound pressure in the presence of transmitted ultrasonic waves, the frequency of the transmitted ultrasonic waves, the transmission rate thereof, the aperture of a probe for transmission, and the focus of the transmitted ultrasonic waves must be taken into account. However, prior arts have not taken such a point into consideration.

Diagnostic ultrasound system using harmonic echo imaging


A particle sedimentation apparatus includes a rotation body rotatable about a rotation axis and a separation chamber formed in the rotation body, to cause sedimentation of particle suspension in the separation chamber upon rotation of the rotation body. The particles accumulate in a radially outward region of the separation chamber. A flow-rate-determining inflow channel having azimuthal path length with an inflow channel inlet and an inflow channel outlet is formed in the rotation body, the inflow channel inlet being arranged radially further inwardly than the inflow channel outlet, the inflow channel outlet being fluidically connected to the separation chamber and formed to introduce particle suspension into the separation chamber upon rotation of the rotation body. Furthermore, an outflow channel is formed in the rotation body with an outflow channel inlet and an outflow channel outlet, to at least partially drain supernatant liquid formed by sedimentation from the separation chamber.

The preparation of samples usually is the first step of many bioanalytical protocols on real samples, such as blood, food, or environmental samples. Often, a particular species of biomolecules is isolated from a mixture of other molecules and particle constituents and transferred into a new buffer. The invention described here concerns the centrifugal separation of particles from a suspension in which particles are suspended in a liquid.
Separating particles from suspensions by means of centrifuges represents an established standard method in laboratory analyses. Particles in suspension, such as the cellular proportion of blood, sediment under the influence of the centrifugal gravitational field according to their distribution of density. The particle suspension, for example the blood, is introduced into a rotating reservoir 10 (FIG. 1), which is rotatable about a rotation center 12. During rotation, for example at an angular velocity ω, a stack of three phases forms in the reservoir 10, as shown in FIG. 1. A particle-free supernatant liquid forms radially inwardly, whereas at the radially outward edge a phase of sedimented particles 16 forms due to its mass density, which is increased as opposed to the liquid. In the sedimentation, this outer phase 16 mainly represents a sediment of more dense, cellular blood constituents, consisting of cells. Between the particle-free supernatant 14 and the sediment, there initially still is a phase 18 consisting of particles in suspension. After a certain time, the phase 18 transitions into the particle-free supernatant 14 with its liquid proportion and into the sediment 16 with its particle proportion.
The complete transition is reached after a time t1, wherein at this time instant an equilibrium state is present in that particles and solution are separated from each other as far as possible, except for some liquid residue in the spaces between the sediment particles. As shown in FIG. 1, the interfaces between particle-free supernatant 14 and suspension 18, as well as between suspension 18 and sedimented particles 16 converge until the equilibrium is finally reached at the time instant t1. In FIG. 1, the distribution in the reservoir is shown at a time instant t0.
Following the sedimentation, the particle-free supernatant liquid is poured off the precipitate or taken out of the reservoir by means of a pipette.
Miniaturized analysis systems on rotating discs offer the simple possibility to sediment particles from suspensions, due to their centrifugal drive. But for further integrated process execution, in most cases the spatial separation of both phases from each other is required. The concluding procedure of pouring out or pipetting off, in particular, is difficult to represent technologically on this integrated microsystem, because the macroscopic method would correspond to a tilt of the channel axis with respect to the direction of the centrifugal force. Due to the further rotation axis, however, this could only be effected with significantly increased instrumental effort.
As it has been mentioned, an important goal with medical diagnostic systems is the integration of complete process chains from the preparation of blood to an analytical result. Various, so-called "lab on a chip" systems have been proposed, see M. J. Madou and G. J. Kellogg, Proc. Of SPIE, vol. 3259, 1998, pages 80-93; G. Thorsen, G. Ekstrand, U. Selditz, S. R. Wallenborg, and P. Andersson, Proc. Of UTAS 2003, eds. M. A. Northrup, K. F. Jenson, D. J. Harrison, Kluwer Academic, 2003, pages 457-460.
Various microfluidic structures on centrifugal platforms are known. These include, among others, sample preparation, flow control by capillary valves and further fluidic networks, see WO 0079285, WO 2004058406, WO 03024598. Furthermore, systems for the separation of blood into plasma and cells in non-centrifugally driven Microsystems are known, see WO 2004074846, WO 2004029221.
WO 2004/061413 A2 concerns a microfluidic apparatus enabling separation of particles in a liquid sample, and particularly of blood into its components, for further analysis. The separation into red blood cells and plasma takes place during few seconds after the blood sample has been introduced into a separation chamber by centrifugal force. A radially passing feed channel, leading into the separation chamber at a radial internal wall, is provided. The separation mechanism here critically depends on surface interactions.
From DE 3723092 C1, a passage centrifuge for industrial production of proteins from human blood plasma is known, in which plastic containers are arranged, which are arranged concentrically with respect to each other in a centrifugal drum, are mutually connected in the bottom region by at least one channel, form annular or ring-segment-shaped chambers, and of which the plastic container or containers facing the rotational axis of the centrifugal drum have an inflow port and the plastic container or containers provided in the outer region of the centrifugal drum have an overhead outflow channel.
In U.S. Pat. No. 4,010,894, a fluid container for use in a centrifugal system for separating the different constituents of blood is described. The container includes two circular layers of flexible material, having center openings. The outer peripheral edges and the inner annular portions around the center opening are connected to each other. Concentrically arranged inner and outer annular channels are formed at the outer peripheral portion of the assembly. Radial arcuate portions are connected to each other, whereby interrupted annular channels are formed. At a first end of the inner annular channel, an inlet tube is provided, which extends outwardly from the center opening and communicates with the first end of the inner annular channel. At the outlet or second end of the inner annular channel, a radially extending interchannel connector is provided, which comprises a sealed portion extending between the adjacent ends of the inner and outer annular channels. At this outlet end of the inner channel, also a radially enlarged region is provided, which acts as a first collecting chamber, into which an outlet tube extending from the inner opening leads. A second outlet chamber is provided at the outlet end of the outer annular channel.

Particle sedimentation apparatus and method for performing particle sedimentation


A nuclear reactor core comprising fissile material is surrounded by a core former. The core former comprises one or more single-piece annular rings wherein each single-piece annular ring comprises neutron-reflecting material. In some embodiments the core former comprises a stack of two or more such single-piece annular rings. In some embodiments the stack of single-piece annular rings is self-supporting. In some embodiments the stack of single-piece annular rings does not include welds or fasteners securing adjacent single-piece annular rings together. A core basket may contain the nuclear reactor core and the core former, and in some embodiments an annular gap is defined between the core former and the core basket. In some embodiments the core former does not include welds and does not include fasteners.

The following relates to the nuclear power reactor arts, neutron reflector arts, and related arts.
In a nuclear reactor, fissile material is arranged in the reactor such that the neutron flux density resulting from fission reactions is sufficient to maintain a sustained fission process. In a commercial reactor, fissile material is typically provided in the form of fuel rods mounted in modular, elongated fuel assemblies which are generally square or hexagonal in cross section. A plurality of such fuel assemblies are arranged together to form a reactor core which is contained inside a cylindrical stainless steel core basket. This entire assembly, in turn, is mounted inside a pressure vessel. In a typical configuration, reactor coolant flows downward in an annular space between the core basket and the pressure vessel, reverses direction in a lower plenum of the vessel, flows upward through openings in a lower end plate at the bottom of the reactor core, and upward through the fuel assemblies where it is heated by the reactor core. The heat extracted by the reactor coolant from the core is utilized to generate electricity thereby lowering the temperature of the reactor coolant which is recirculated through the reactor in a closed loop. In boiling water reactor (BWR) designs, the primary coolant boils inside the pressure vessel and the resulting primary coolant steam is piped through a recirculating loop to drive a turbine. In pressurized water reactor (PWR) designs the primary coolant remains in a subcooled liquid state and heats secondary coolant in an external steam generator, and the secondary coolant drives a turbine. In a variant PWR design, the steam generator is located inside the pressure vessel (i.e., an integral PWR) and a secondary coolant circuit flows into the pressure vessel to feed the steam generator.
In the fission process, free neutrons are generated. In a thermal nuclear reactor, these neutrons are slowed, i.e. thermalized, by ambient water which is advantageous as thermalized neutrons are more likely to stimulate additional fission events as compared with faster neutrons. However, neutrons originating near the outer boundary of the reactor core may travel outside the reactor core and be lost. To improve overall efficiency and to increase burn rate for the outer fuel assemblies, it is known to include a core former, or radial reflector, between the reactor core and the core basket. The objective is to reflect neutrons traveling out of the core back toward the core to enhance burn of the fuel assemblies.
The welds, bolts, or other fasteners of the radial reflector experience high radiation flux, and can be prone to damage or failure due to the harsh operating environment with the reactor. Repair of any such damage is difficult or impossible due to the extremely radioactive environment. Moreover, the radial reflector can impede natural circulation around the reactor core, which may be problematic for any emergency core cooling system (ECCS) that relies upon natural circulation. In some instances radial reflectors are known to cause jetting of coolant laterally onto the fuel assemblies. Jetting is generally undesirable as excessive wear may result over time.

Self-supporting radial neutron reflector


A covert all-weather roving camera security system includes a monorail track, at least one self-propelled trolley able to move itself back and forth continuously along the monorail track, and a plurality of surveillance cameras attached to the trolley. A housing completely encloses the monorail track and the trolley and has a sunshield on its top to protect the cameras from overheating and a filtered window on its sides and bottom to prevent human eyes from seeing in the housing while permitting the cameras to see out.

Security camera installations are known in which stationary cameras are placed every 50 meters or so along a fenced perimeter to patrol the perimeter. In such systems, it is costly to provide the infrastructure and power cable to accommodate a lengthy perimeter. Also, because the cameras are stationary, there may be blind spots along the perimeter where corners are turned and the fence goes up and down hills. Another drawback is that the cameras are positioned to look down the fence line. If conventional chain link fencing is used, as the cameras look down the fence line the chain link mesh obstructs the line of sight. In addition, if the perimeter is heavily wooded, as the cameras look down the fence line they may fail to detect intruders who would clearly stand out if the fence were viewed head on.

The United States of America as represented by the Secretary of the Army


Thermomechanical pulp is an important process for producing fibrous mass used in papermaking. A two-level control strategy that stabilizes and optimizes the refining process has been developed. The Stabilization layer consists of a multivariable model predicative range controller that regulates the refiner line operations. The Quality Optimization layer provides the pulp quality control as measured by an online pulp quality (freeness, fibre length) sensor. This control startegy leverages the natural decoupling in the process. The modular design technique is able to handle multiple refiner lines that empty into a common latency chest. A global optimizer is also used to integrate and coordinate the two layers for enhanced constraint handling.

Processes for making paper pulp consist in reducing the raw materials to separate fibers containing a greater or lesser amount of cellulose depending on the qualities which the pulp produced is required to have. The processes essentially consist of grinding operations, which are basically mechanical, which may be combined with more or less powerful delignification operations, which are basically chemical.
Depending on the relative importance of the two treatments, it is possible to distinguish five major types of pulp:
(1) Mechanical pulp, obtained by grinding without any chemical treatment beforehand of the raw material;
(2) Thermo-mechanical pulp, obtained by grinding under pressure, which is made easier by steaming the raw material beforehand to soften the lignin;
(3) Mechano-chemical pulp, obtained by grinding in combination with in situ or ex situ preliminary treatment of the raw material with chemical reagents;
(4) Semi-chemical pulp, obtained by grinding raw material which is previously subjected to partial chemical "cooking" under pressure; and
(5) Chemical pulp, where the chemical processing is much more powerful and produces both the delignification and the major part of the reduction to fiber.
Refiner mechanical pulp (RMP) is produced by the mechanical reduction of wood chips (and sometimes sawdust) in a disc refiner. The process usually involves the use of two refining stages operating in series, i.e., two-stage refining, and produces a longer-fibered pulp than conventional ground wood. As a result, it is stronger, freer, bulkier, but usually somewhat darker in color, than stone ground wood. Thermomechanical pulping (TMP) was the first major modification of RMP, and is still employed on a large scale to produce high-tear pulps for newsprint and board. This process involves steaming the raw material under pressure for a short period of time prior to and during refining. The steaming serves to soften the chips, with the result that the pulp produced has a greater percentage of long fibers and fewer shives than RMP.
It is becoming increasingly important to produce TMP pulp that is both uniform and of a high quality. Papermakers desire to optimize paper machine operations, and in some instances to replace the expensive kraft furnish. Even though advanced process control has gained general acceptance in the pulp and paper industry, the thermo-mechanical pulping process is still under manual control in most pulp mills. Reliance on manual control stems primarily from the complexity of the TMP process, which is highly interactive requiring control and variable inputs from many sections of the refining process. Additionally, control of the TMP process is further complicated as blow-line consistency in most cases is not measured using an online sensor. Pulp quality descriptive variables such as fiber length and freeness are also measured infrequently.
In order to produce high quality thermo-mechanical pulp, the refining process must be under tight control. Closed loop control of a TMP refiner system is one of the most complex and challenging control problems in a pulp mill. The process is inherently multivariable, exhibiting strong interactions. In addition, the bandwidth of the process outputs is spread over a wide frequency range. For example, the open loop response between the primary plate gap to the primary motor load and final pulp freeness is about 2 minutes and about 90 minutes, respectively. The refining process is also complicated by non-stationary process dynamics due to wear of the refiner plates.
In the past, TMP controller design was attempted using single-loop PID based decentralized control architecture. The choice of decentralized architecture was appealing as it was easy to understand by mill personnel and simple to implement using the existing distributed control system (DCS). Proportional-integral-derivative (PID) based control strategy is acceptable for regulation of local control loops such as flow and pressure regulation, but a PID controller cannot handle complex multivariable dynamics. In addition, a PID controller can only control a single process output. However, to adequately control pulp quality at least two variables such as, for example, Canadian standard freeness (CSF) and mean-fiber length (MFL) must be controlled. Since these variables are physically linked, they cannot be independently controlled to arbitrary targets, instead these variables must be controlled within an operator defined quality window. The quality window is defined by setting the upper and lower limits on the pulp quality variables. In order to handle this control problem a multivariable controller is required that can also handle process constraints. Constrained model based predictive control (MPC) is a natural candidate in the process industrial. MPC provides a unified framework to efficiently handle complex process interactions and constraints. MPC technology has also gained industrial acceptance and it can be easily integrated into existing mill DCS platforms.
The use of MPC to control a refiner system has been presented by Du, H., entitled, Multivariable predictive control of a TMP plant, Ph.D. dissertation, UBC, Vancouver, BC, Canada, 1998. The study was presented at a theoretical level that demonstrated the need to control the refining intensity. However, no attempt was made to directly control the pulp quality. Other work by Strand, W. C., et al., IMPC 2001 discusses the use of MPC but the details of the control strategy are not disclosed.

System and method for controlling a thermo-mechanical wood pulp refiner


The present invention is directed to the incorporation of functionalized polyethylenes, in amount of about 1% to 95% by weight based upon the weight of the total crosslinkable material, into ethylene alpha olefin elastomers, such as EPDM elastomer compositions, which are crosslinked by peroxides, which results in improved properties, such as hardness and modulus of elongation, and can result in improved higher abrasion resistance, wear resistance, coefficient of friction, tensile strength, and other properties through a broad temperature range, which are beneficial to power transmission products, such as power transmission belts.

The present invention is directed to improved ethylene-alpha-olefin elastomers, especially EPDM-based elastomers, for use in manufacturing power transmission products, such as power transmission belts, timing belts, and the like. More specifically, the invention is directed to such elastomers which incorporate certain types of functionalized polyethylenes which result in belts having enhanced physical properties.
Power transmission belts are known. See for example, U.S. Pat. No. 6,561,937 (Wegele); U.S. Pat. No. 6,695,734 (Hedberg et al); U.S. Pat. No. 5,610,217 (Yarnell et al) and U.S. Pat. No. 6,251,977 (Georget et al). Proposals have already been made on numerous occasions to use EPDM (ethylene propylene diene terpolymer) elastomers cured by organic peroxides in the manufacture of power transmission belts, because of the qualities and advantages of such elastomers such as cost, operating temperature range, and ability to withstand oxygen and ozone, such EPDM-based elastomers having additives which improve their dynamic properties such as resistance to fatigue and to wear, their breaking strength, and their modulus of elasticity, and also their adhesion to traction cords, which additives are generally constituted by metallic salts of α,β-unsaturated organic acids (in particular zinc methacrylate) plus reinforcing fillers such as carbon black and possibly fibers, e.g. aramid fibers. For example, the Yarnell '217 patent teaches the use of α,β-unsaturated organic acids in peroxide cured EPDM elastomers. The Georget et al '977 patent teaches the inclusion, in peroxide cured elastomers, of an elastomer grafted with maleic anhydride which reacts with the α,β-unsaturated organic acid metallic salt included in the composition to reinforce the curing of the EPDM-based elastomer and to improve its dynamic characteristics, such as in particular its modulus of elasticity, its breaking strength, and its hardness. The elastomer grafted with maleic anhydride can be a polybutadiene, polyisoprene, polypropylene, or an ethyl vinyl acetate (EVA) copolymer, and the elastomer is used as a power transmission belt.
Oxidized polyethylenes are known and are taught by U.S. Pat. Nos. 2,683,141 and 3,060,163 to Erchak. They are used to form stable, translucent emulsions for use in floor waxes, in coatings for asbestos shingles, paper and textiles, and in inks for application to various surfaces. They have been incorporated into thermoplastic polypropylene compositions containing EPDM compositions, such as those described in U.S. Pat. No. 4,990,568 to Benefield et al. In Benefield a thermoplastic polypropylene is modified with EPM or EPDM and an oxidized or carboxylated polyolefin, in at an amount of 2 to 20% of the elastomer, to improve the problem of adherence of coatings applied to the surfaces of articles formed from the thermoplastic elastomers.

Power transmission products having enhanced properties


In a management of taxonomic information, a name that specifies an organism is identified. Based on the name and a database of organism names or classifications, another name that specifies the organism and that represents a link between pieces of biological identification information in the database, or a classification for the organism, is determined. Based on the other name or the classification, information associated with the organism is identified.

This invention relates to managing taxonomic information.
With modern advances in computer technology and network and Internet technologies, vast amounts of information have become readily available in homes, businesses, and educational and government institutions throughout the world. Indeed, many businesses, individuals, and institutions rely on computer-accessible information on a daily basis. This global popularity has further increased the demand for even greater amounts of computer-accessible information. However, as the total amount of accessible information increases, the ability to locate specific items of information within the totality becomes increasingly more difficult.
The format with which the accessible information is arranged also affects the level of difficulty in locating specific items of information within the totality. For example, searching through vast amounts of information arranged in a free-form format can be substantially more difficult and time consuming than searching through information arranged in a pre-defined order, such as by topic, date, category, or the like. Due to the nature of certain on-line systems much of the accessible information is placed on-line in the form of free-format text. Moreover, the amount of on-line data in the form of free-format text continues to grow very rapidly.
Search schemes employed to locate specific items of information among the on-line information content typically depend upon the presence or absence of key words (words included in the user-entered query) in the searchable text. Such search schemes identify those textual information items that include (or omit) the key words. However, in systems, such as the World Wide Web ("Web"), or large Intranets, where the total information content is relatively large and free-form, key word searching can be problematic, for example, resulting in the identification of numerous text items that contain (or omit) the selected key words, but which are not relevant to the actual subject matter to which the user intended to direct the search.
As text repositories grow in number and size and global connectivity improves, there is a need to support efficient and effective information retrieval (IR), searching, and filtering. A manifestation of this need is the proliferation of commercial text search engines that crawl and index the Web, and subscription-based information mechanisms.
Common practices for managing such information complexity on the Internet or in database structures typically involve tree-structured hierarchical indices such as the Internet directory Yahoo!™, which is largely manually organized in preset hierarchies. Patent databases are organized by the U.S. patent office's class codes, which form a preset hierarchy. Digital libraries that mimic hardcopy libraries support subject indexing inspired by the Library of Congress Catalogue, which is also hierarchical.
Querying or filtering by key words alone can produce unsatisfactory results, since there may be many aspects to, and often different interpretations of, the key words, and many of these aspects and interpretations may be irrelevant to the subject matter that the searcher intended to find.
For example, if a wildlife researcher is attempting to find information about the running speed of the jaguar by submitting the query "jaguar speed" to an Internet search engine, a variety of responses may be generated, including responses relating to Jaguar® cars and a Jaguar sports team, as well as responses relating to the jaguar animal.
If an index such as Yahoo!™ is used, the user can seek documents containing "jaguar" in the topical context of animals. It is labor- and time-intensive to maintain such an index as the Web changes and grows.
Biocentric information is information associated with at least one instance of something that is or was alive ("biotic entity" or "organism"), and, as illustrated in FIGS. 1-2, may include human observations recorded to physical media, physical specimens, and other biocentric data items that libraries store and that museums collect, including photographs, slides, and annotations on physical specimens. Libraries house vast collections of publications, many of which refer to the observations and recordings about the natural world (see, e.g., FIG. 3).
As shown by example in FIG. 4, biocentric data items can be electronic objects that represent biocentric information in an electronically accessible way. Biocentric data items can be derived from biocentric information in a variety of formats.
Biocentric files may be served through applications, as illustrated by examples in FIG. 5. Observations may be recorded in tables that are served via database management tools. A suite of software tools may allow table data to be flexibly delivered to the Web. Accordingly, information on specimen collections, bibliographic references, and field observations of organisms can be recorded and retrieved.
Multimedia objects having audio, illustrations, photographs, or video (sometimes referred to as "binary large objects" or "BLOBs") may be served by many applications. FIG. 6 illustrates an example of a combination of database and image server used to serve photos to the Web. The images are served through the image data server, which communicates with the database server to locate and serve the associated text annotations.
Full-text documents represent a resource of biocentric information. Books, journals, monographs, and manuscripts are historic means of communicating and storing knowledge of the natural world. The recording, parsing, and serving of full-text is a complicated endeavor. Technologies known as Standard Generalized Markup Language (SGML) and Extensible Markup Language (XML) offer a flexible infrastructure for serving full-text data, as diagrammed in FIG. 7.
Applications reside on host computers that serve that biocentric data through network protocols. Often these hosts are specialized for a particular task or group of tasks, as illustrated by examples in FIG. 8. One server may supply many different services or the services may reside on more than one machine. The information that is served may reside at a particular location to take advantage of services on the host or proximity to a data manager to facilitate management.
Multiple hosts can be organized within logical subnetworks that can be viewed as a logical entity known as a domain, as shown by example in FIG. 9. A domain may represent a collection of hosts, each with its own collection of applications, each with its own collection of biocentric data.
FIG. 10 illustrates by example that relationships exist between domains and applications within domains concerning the biocentric data. A domain is a user-defined arbitrary collection of applications. For example, an institution may have a library catalog application and an on-line encyclopedia application, both of which rely on animal names.
Scientific interest in the creation of a unified catalog of the 1.75 million known species of living organisms has been recognized by Species 2000 and North America's Integrated Taxonomic Information Systems (ITIS).
Such an attempt to organize biocentric information is put forth in the context of the large number of species, the variation within species, and the expression of individual and species information with historical and geographical dimensions, from scales ranging from the molecular to the ecosystem, and modified as a function of a myriad of potential biotic and abiotic interactions. Furthermore, much of the known information was collected in a pre-electronic format, and the ranks of the custodians of much of that information (primarily taxonomists) are not being fully replenished as the custodians retire. Bioinformatics tools such as GenBank® are available to deal with molecular data. However, data on biodiversity can be difficult to assemble. The challenge of making biodiversity information available electronically is of such a magnitude that it has been described as requiring a "mega science" response. Federal and intergovernmental programs such as Global Biodiversity Information Facility (GBIF), Partnerships for Enhancing Expertise in Taxonomy (PEET), Australian Biological Resources Study (ABRS), and Species 2000 have emerged to address this problem. One strategy is based on assembling large databases.
Facilities that have been proposed include the following. A GBIF connects smaller databases and creates a directory of the three billion specimens in museums and seed banks. GBIF is an initiative of the United Nations Environment Programme/Organization for Economic Cooperation and Development (UNEP/OECD) and inter-governmental programs committed to documenting the diversity of life. GBIF includes Species 2000 and the Expert Taxonomy Institute (ETI) as associates.
Species Analyst is a biodiversity site that provides access to natural-history databases to promote taxonomy in the United States. Species Analyst seeks to integrate biodiversity information through the Web.
Species 2000, which aims to index all the world's known species, has data on 250,000 species in a rigid database structure. Species 2000 is a focal point for many biodiversity enterprises.
Deep Green presents data on the genetics and evolution of plants.


A system for delivering streamed content over a large digital network such as the Internet. Distributed functionality executes on nodes in the network to achieve functions such as assigning partner nodes for transfer of content to or from a target node, scheduling transfer operations among nodes, adding or removing nodes from the network, maintaining security, and other operations. Different embodiments may use one or more of the functional features. In a preferred embodiment, video content is segmented and streamed through multi-path routing. An overlay network uses nodes in partnership groups so that a target node can obtain segments from multiple sources. Partner nodes can provide the segments within a given time window, including simultaneous delivery from multiple partner nodes, so that a more reliable data stream is supported.

The Internet has proven to be very useful and effective at transferring information over large distances and to many users. However, certain "high bandwidth" types of information such as video or image data can tax or exceed the Internet's ability to deliver the information in a timely and reliable manner. For example, one type of high bandwidth data, or "content," includes streamed video where the video content is delivered in real time. Such real time delivery typically requires that the information be received at multiple destinations within a small time window so that the information is received at or near the time it is displayed or presented to a user. The delivery of real time video content is made more difficult in "multicast" applications where a streamed video program is simultaneously provided to many viewers.
Attempts have been made to improve the Internet's ability to transfer large amounts of information, such as large files. Such attempts include using peer-to-peer transfers as opposed to client-server transfers so that a receiver of the content is not limited to one or a few sources of the content. This is an approach used, for example, in a popular file-sharing system referred to as "Bittorrent." However, the Bittorrent approach may not work well for streamed content as the absence of one part of a file can cause dropouts or artifacts in a real time display of the content.
Streamed content is also vulnerable to service fluctuations over the network's delivery route. Because of the technical problems encountered when large amounts of information are sent to many destinations, improvements in the delivery of high bandwidth content over large networks such as the Internet are desired.

Distributed system for delivery of information via a digital network


A communication system includes a scanning receiver coupled to a first antenna, a plurality of repeaters coupled to a second antenna, wherein each repeater operable on any channel in a band, and a computer coupled to each repeater for controlling the operation of each repeater and coupled to the scanning receiver for obtaining traffic information from the receiver and storing the information in memory. The memory also contains a table of channels and station IDs, wherein a station ID is associated with a particular channel. Each repeater operates on an available channel, as indicated by the traffic information, using the station ID associated with the channel. The repeaters themselves can be used for obtaining traffic information, eliminating the scanning receiver. The repeaters do not have final amplifiers. Instead, a low level combining circuit couples the signals from each repeater to a single linear amplifier.

This invention relates to a repeater system for enabling mobile or portable radio stations to communicate with each other and, in particular, to a communication system that increases usage of existing channels in a band without increasing conflicting requests or "collisions."
The frequency spectrum is like land, minerals, or fossil fuel, in that it is a finite resource. Meetings are held internationally to allocate portions of the spectrum among the many claimants. Various segments or bands of the frequency spectrum are dedicated to mobile communications, typically using a repeater. Other bands are allocated to federal, state, or local governments, amateur radio, and utilities, for example. Recently, the government of the United States discovered that auctioning licenses to operate in portions of the frequency spectrum was a spectacular source of revenue. Providers of cellular telephone and other communication services anxiously purchased as many site licenses and channels as possible, viewing the licenses as an investment. The view is reasonable because, once taken, there are no more channels available.
A repeater is a receiver-transmitter combination for receiving a signal at one frequency and simultaneously re-transmitting the same signal on a second frequency. Depending upon application, the transmitted frequency may be relatively close to the received frequency, e.g. 600 khz., or greatly displaced from the received signal. Depending upon application, frequency, and government regulation, the transmitter in a repeater may be relatively powerful, hundreds of watts, or may be rated at just a few watts.
Commercial two-way radio communication has evolved into two different techniques for mobile operation, cellular and specialized mobile radio (SMR) or dispatch service. Cellular systems use several repeaters dispersed in a geographic area and operating at low power to keep propagation relatively short, e.g. within a radius of less than ten miles. The local area covered by each repeater overlaps the local areas covered by neighboring repeaters, forming overlapping "cells" of coverage. A subscriber traveling from one cell to another cell is automatically switched from one repeater to another by a computer coupled to the repeaters by microwave link, optical fiber, or wire.
Because propagation is short, the frequencies used by one repeater can be used by a non-neighboring repeater without interference, thereby serving more subscribers in a given geographic area. Re-using assigned frequencies in a geographic area provides much more efficient use of the limited resource.
SMR uses a powerful repeater, usually located at the highest available elevation in a geographic area. The repeater is coupled to an omni-directional antenna to cover the entire geographic area, enabling dispatchers to communicate with a fleet of vehicles in the geographic area and enabling the vehicles to communicate with each other. U.S. application Ser. No. 498,510, filed Jul. 5, 1995, and owned by the owner of this invention, discloses a system for increasing use of an SMR repeater by defining a plurality of cells radially extending from the antenna.
Despite these techniques in the fields of cellular radio and SMR, the number of channels available will become less than the number needed for all potential users. Providing service even for current users requires a large number of repeaters, which are very expensive to install and to maintain. Part of the problem is that repeaters available today operate on a small number of frequencies and are designed to handle the maximum anticipated traffic. As such, many repeaters are often idle for long periods when traffic is light. The problem is compounded if a repeater is held in reserve to cover failures due to lightning or some other cause. This further increases the number of repeaters required and, by definition, the reserve repeater is idle.
In view of the foregoing, it is therefore an object of the invention to increase the utilization of existing mobile communication equipment.
A further object of the invention is to provide a communication system that makes more efficient use of allocated channels and transmission sites.
Another object of the invention is to provide a communication system that can serve more than one licensee.
A further object of the invention is to provide a system that enables small service providers to increase the number of subscribers that can be serviced.
Another object of the invention is to provide a repeater back-up function without requiring an additional repeater.
A further object of the invention is to increase usage of relatively idle channels in a communication service area.


A fuel-cell system with a fuel battery comprising more than one fuel cell having a purge gas passage connecting the fuel battery to a purge gas cylinder, a discharge passage connecting the fuel battery to the exterior, solenoid valves each installed in the passages, and an electronic control unit that opens the solenoid valves to open the passages to supply the purge gas to the fuel battery such that residue in the fuel battery is purged to the exterior by the purge gas. The control unit opens the valves at a time interval determined from an output of a current sensor to conduct purge at optimum timing for the battery operating state so as to prevent accumulation of residue in the fuel battery, while preventing repetition of unnecessary purges. Alternatively, manual valves are provided to be manually opened by an operator to open a fuel gas supply passage to supply the fuel gas such that residue is purged by the fuel gas through the discharge passage, thereby enabling fuel supply and purge of residue at starting of power generation, without using an external power source.

1. Field of the Invention
This invention relates to a fuel-cell system having a fuel battery comprising more than one fuel cell that changes chemical energy of a fuel and oxidant to electric energy.
2. Description of the Related Art
Retention and/or accumulation of nonreactant gas and/or generated water in a fuel battery lowers the ability to generate power. The practice is therefore to purge the fuel battery of nonreactant gas and/or generated water at regular time intervals, while also monitoring the generated voltage of the fuel battery and carrying out a supplementary purge whenever the generated voltage falls below a predetermined level, as disclosed, for example, in Japanese Laid-open Patent Application No. 2000-243417.
The amount of nonreactant gas and generated water present in a fuel battery varies with the operating state of (load on) the fuel battery. When purges are programmed to be conducted at predetermined time intervals (time periods between consecutive purges) as in the prior art, however, purge is not always performed at the optimum time point. This may result in accumulation of retained nonreactant gas and/or generated water because purge is not carried out when necessary or in repeated unnecessary purges.
On the other hand, the method of conducting purges when the output voltage falls below a predetermined level is also liable to result in repeated unnecessary purges when the fuel battery is connected to a high-load external piece of equipment and the output voltage is stable at a low level.
Aside from the above, when the operation (power generation) of a fuel battery is terminated or stopped, nitrogen and other nonreactant gases may be retained in the fuel battery owing to air flowing in from the air electrode through the electrolytic membrane. In addition, generated water produced in the course of operation sometimes collects to cause water clogging of the passages and diffusion membranes. When such a situation arises, fuel (hydrogen gas) supplied to start power generation of the fuel battery is blocked by the retained gas and/or water and does not reach the fuel cell electrodes, occasionally making it impossible to obtain a desired electromotive force.
It is therefore a conventional practice to discharge (purge) residue from a fuel battery when the operation is to be started, as disclosed, for example, in Japanese Laid-open Patent Application No. 2001-216988.
Most purge systems for discharging residue are composed of a passage (piping/tubing) communicating with the exterior of the fuel battery and a solenoid valve for opening and closing the passage. Moreover, the fuel supply system for supplying fuel (hydrogen gas) to the fuel battery is generally composed of a passage that connects the fuel battery to a gas cylinder charged with fuel gas under high pressure and a solenoid valve for opening and closing the passage. Since solenoid valves are used in the fuel supply and purge systems, an external power source such as a battery is required when the power generation is started. When the fuel battery is used as a portable power generating unit, therefore, portability is degraded by the larger volume and weight of the unit.


In a communication system, and in particular a wireless Orthogonal Frequency Division Multiplexing (OFDM) communication system, the present invention provides systems for synchronizing data transmitted across a channel. The present invention may be used in a Multi-Input, Multi-Output (MIMO) system in which the data is transmitted from any number of transmitting antennas and received by any number of receiving antennas. The number of transmitting and receiving antennas does not necessarily have to be the same. Circuitry is provided for synchronizing the data in both the time domain and frequency domain. Time synchronization involves coarse time synchronization and fine time synchronization. Frequency synchronization involves coarse frequency offset estimation, fine frequency offset estimation, and frequency offset correction.

In wireless communication systems, recent developments have been made using technologies wherein multiple signals are simultaneously transmitted over a single transmission path. In Frequency Division Multiplexing (FDM), the frequency spectrum is divided into sub-channels. Information (e.g. voice, video, audio, text, etc.) is modulated and transmitted over these sub-channels at different sub-carrier frequencies.
In Orthogonal Frequency Division Multiplexing (OFDM) schemes, the sub-carrier frequencies are spaced apart by precise frequency differences. Because of the ability of OFDM systems to overcome the multiple path effects of the channel, and to transmit and receive large amounts of information, much research has been performed to advance this technology. By using multiple transmitting antennas and multiple receiving antennas in OFDM systems, it is possible to increase the capacity of transmitted and received data while generally using the same amount of bandwidth as in a system with one transmit and one receive antenna.
OFDM technologies are typically divided into two categories. The first category is the Single-Input, Single-Output (SISO) scheme, which utilizes a single transmitting antenna to transmit radio frequency (RF) signals and a single receiving antenna to receive the RF signals. The second category is the Multi-Input, Multi-Output (MIMO) scheme, which uses multiple transmitting antennas and multiple receiving antennas.
In typical communication systems, training symbols, or preamble, at the beginning of data frames, are usually added as a prefix to the data symbols. The data symbols, of course, include the useful data or information (e.g., voice, data, video, etc.), which is meant to be transmitted to a remote location. The training symbols in SISO systems are used to provide synchronization of the received signals with respect to the transmitted signals, as well as to provide channel parameter estimation.
Although training symbols used for SISO systems can be used to provide synchronization in a MIMO system, the training symbols cannot provide for channel parameter estimation in the MIMO system. In fact, no method or apparatus exists for MIMO systems that are capable of providing time and frequency synchronization as well as channel parameter estimation. Thus, a need exists for a method and apparatus that is capable of providing time and frequency synchronization in MIMO systems and can further perform channel estimation.

Time and frequency synchronization in multi-input, multi-output (MIMO) systems


A compound of Formulae (1), (2) or (3), A1-Ph (1) or A1-Ar-A2 (2) or A1-(A2)A′-A3 (3) wherein A1, A2 and A3 are selected from Formulae 4, 5 and 6:

CXCR4 chemokine receptors, are found on the surface of immune cells, and interact with the specific natural ligand, known as CXCL12 or stromal cell-derived factor 1α (SDF-1α). They have been revealed to play a role in a number of disease states. For example the CXCR4 SDF-1α system has involvement in cancer progression and metastasis, and in the development of rheumatoid arthritis. CXCR4 and CCR5 co-receptors have been identified as the entry route for HIV into cells, providing a new therapeutic approach to treatment by entry inhibitor drugs rather than the current preference for reverse transcriptase and protease inhibitors. An object of the present invention is to provide new antagonists for the CXCR4 co-receptor.
This invention may provide novel compounds that selectively bind to chemokine receptors based on cross bridged macrocycles. The compounds may incorporate metal ions and form stable complexes prior to administration.
It is an object of this invention to provide examples of bridged azamacrocyclic derivatives that show specific chemokine receptor binding.

Antiviral macrocycle derivatives and metal complexes, incorporating bridged macrocycles

Abstract: or a salt whereof; wherein Ar is selected from the group consisting of 1,2-phenyl, 1,3-phenyl and 1,4-phenyl optionally substituted with one or more methyl groups; m and n are independently integers from 0 to 1; Ph is phenyl, optionally substituted with one or more methyl groups; Ar1 is trisubstituted phenyl optionally substituted with one or more phenyl groups; and R1, R2 and R3 are independently selected from the group consisting of H, Me and linear chain C2-C4 alkyl.


The current invention concerns a method and apparatus for stretching and repitching an elastic member for attachment to a moving substrate, the elastic member being stretchable in at least a longitudinal direction and said elastic member in an essential non-stretched condition comprising an initial length along said longitudinal direction, the method comprising the steps of: (1) providing the elastic member in essentially non-stretched condition to a set of repitching members with an initial supply pitch, said set of repitching members comprising at least a first repitching member and a second repitching member, and optionally one or more repitching members arranged between said first and said second repitching member; (2) receiving said elastic members arranged in non-stretched condition between said set of repitching members, whereby the distance between the first and the second repitching member corresponds to the initial length of the elastic member; (3) moving at least said first and said second repitching members following trajectories diverging from each other, thereby stretching said elastic members arranged between the repitching members to an application length which is longer than the initial length and which corresponds to the length of said elastic member in elastically stretched condition, whereby said repitching members are moved with selectively variable velocity when transferring said elastic members to selectively vary the application pitch of said elastic member in stretched condition on said substrate, the variation of the speed of said repitching members determining the application pitch of said elastic member in stretched condition on said substrate, characterized in that during step (3), said set of elastic members are rotated around a common rotation axis while the elastic member is being stretched from the initial length to the application length. Additionally, the invention concerns a method and apparatus for stretching and repitching an elastic member for attachment to a moving substrate whereby the elastic members are held by repitching members, which are rotated at an essentially constant rotational speed around rotation axes in trajectories, said trajectories being defined by having a different radial distance from the rotation axis to the repitching member rotating around said rotation axis at the application position where the elastic member is attached to the substrate, than at the initial position where the elastic member is received by the repitching members, thereby changing the pitch of the elastic members.

In the manufacturing of stretchable laminates, e.g. for use in hygienic disposables such as diapers, it is common to attach highly elastic members to substrates such as sheets which can be made of nonwoven material. Hereby, the substrates can have different elasticity properties than the elastic members, typically, the substrates have a smaller elasticity. In order for the laminate to be elastic, one option is to stretch the highly elastic member while it is attached to the substrate. As a result, once the attachment process is complete, the elastic member can be allowed to relax, thereby contracting the laminate, including the substrate, and offering the possibility e.g. to take on a certain 2D or 3D shape, or to be stretched during use, or to provide a better fit, etc.
One problem in manufacturing such laminates, i.e. laminates wherein an elastic member is stretched when it is attached to a substrate, is that the elastic members can be provided at a different pitch as the substrate. For instance, in a manufacturing process for diapers pants, an elastic member, e.g. an elastic strip, can be attached to a nonwoven sheet to ultimately form a stretchable front waist region. Herein, elastic strips are provided at a pitch P1, which typically can be the height of the strips, and which is related to the speed V1 of the strips according to V1=P1×n1, wherein n1 is the number of strips per unit of time. The nonwoven sheet can be provided in the form of an endless nonwoven at a speed V2, which can be cut later on in the process into individual articles at a rate of n2 articles per unit of time. Hence the pitch of the nonwoven is P2, whereby V2=P2×n2. In order to attach the strip to the nonwoven, the speed of both components need to be matched: V1=V2. If one strip needs to be attached per article, then n1=n2, and thus P1 needs to be the same as P2. If the initial value of P1 at which the strips are provided is lower than the initial value of P2 at which the nonwoven is provided, at least one of the two pitches needs to be altered. The present invention concerns a method and apparatus wherein the pitch P1 of the elastic members is adapted, typically increased, such that the speeds V1 of the elastic member and V2 of the substrate are matched during the actual attachment step. The term "repitching", within the context of this text, refers to this altering of the pitch of the elastic members.
European patent application EP 2 260 813 A1 discloses a device for forming elastication strips applicable in stretched condition (S′), for example along the waistline of sanitary articles (D) such as diapers and the like, the device including at least one pair of combined drawing members suitable for operating in gripping relation on the ends (A) of the strips to receive the strips themselves arranged bridge-like therebetween in non-stretched condition (S) at an inlet end (I) of the device, where said drawing members are at a first distance corresponding to the length of the strips (S) in non-stretched condition (S). The drawing members are moveable according to trajectories diverging from each other to draw the strips arranged bridge-like therebetween towards an outlet end (O) of the device, where the drawing members are at a second distance, greater than the first distance and corresponding to the length of the strips in elastically stretched condition (S). The drawing members are moved by motor means with selectively variable velocity (K) when transferring the strips between the inlet end (I) and the outlet end (O) to selectively vary the application pitch (P2) of the strips in stretched condition (S′) on the sanitary articles (D). The drawing members operate on the ends of the strips (A) in a gripping relation without fastening or pinching, i.e. through vacuum pressure and/or hooking formations. This document thus discloses a method wherein repitching and stretching of an elastic strip is performed simultaneously.
However, the applicant has observed that the above disclosed method presents a number of disadvantages. One disadvantage is that the thusly formed laminate shows an uneven wrinkling at and around the region where the strip is applied, the uneven wrinkling leading to a distorted appearance of the final product and, more importantly, to a spread in the shape of many final products, leading to possible difficulties in subsequent packaging of a plurality of products and also to a set of products which are intended to be the same but do not look like they are the same.
There remains a need in the art for an improved method and apparatus for repitching and stretching elastic members for attachment to a moving substrate, which aims to resolve at least some of the problems mentioned above.
The invention thereto aims to provide a method and apparatus which ensures that the laminate and/or the final product comprising the laminate assumes the intended shape and/or an even contraction upon relaxation of the elastic member of the laminate.

Apparatus and method for stretching and repitching elastic members


A multibit phase change memory device structured such that a plurality of individual phase change memory devices are aligned in a plan area or vertically, and a method of driving the same are provided. The multibit phase change memory device includes a phase change material layer having a plurality of contact portions being in contact with a heating electrode, and having a plurality of active regions, each active region forming a unit phase change memory device. The phase change material layer may be composed of one material layer in which the plurality of active regions are aligned in plural arrays. Alternatively, the phase change material layer may be composed of a plurality of phase change material layers in which one or plural active regions are respectively aligned in one array. The plurality of phase change material layers may be disposed in a same level of a plan area, or the plurality of phase change material layers may be respectively disposed on different plan areas in a same vertical line.

This application claims the priority of Korean Patent Application No. 10-2004-0089162, filed on Nov. 4, 2004, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a memory device using a phase change material and a method of driving the same, and more particularly, a multibit phase change memory device and a method of driving the same.
2. Description of the Related Art
In recent years, a nonvolatile memory device retaining stored data even with supplied power cut off has been dramatically developed in technology along with the demand increase of portable personal assistants. A flash memory device as a representative nonvolatile memory device is substantially involved in most of the markets for nonvolatile memory devices with the advantage of low costs of production based on silicon processing. However, the flash memory device has drawbacks of requiring a relatively high voltage for data storage and limiting the number of repeated data storage. Accordingly, efforts to overcome the drawbacks for next generation nonvolatile memory devices are actively studied.
The next generation nonvolatile memory devices are roughly classified into two types, i.e., capacitor type memory device and resistor type memory device. A representative example of the capacitor memory device is a ferroelectric memory device using ferroelectric material, and the ferroelectric memory device reads stored data types from the polarization direction of the ferroelectric capacitor. A ferroelectric oxide material is mostly used for the ferroelectric memory device, but recently, the nonvolatile memory device using a ferroelectric organic material is actively researched.
Representative examples of the resistor type memory device are a magnetic tunnel junction memory device and a phase change memory device. The magnetic tunnel junction memory device, namely "magnetic RAM: MRAM", has a structure in which a very thin insulating layer is inserted between two magnetic material layers, and operates to store data by controlling the spin polarization direction of the two magnetic material layers surrounding the insulating layer, and read stored data types from the magnitude of the tunnel current passing through the insulating layer, i.e., the resistance magnitude, in the cases that the spin polarization directions are same or different.
The phase change memory device, namely "phase-change RAM: PRAM", uses the characteristics of the phase change material in which resistance magnitude is changed in accordance with the crystal structure of the material. The phase change memory device stores data by controlling the crystal structure of a phase change material with the appropriate selection of current or voltage application, and reads stored data types from the change of the resistance magnitudes in accordance with the crystal structure of the phase change material.
The various nonvolatile memory devices exemplified as above have their own advantages and disadvantages. For example, ferroelectric memory devices have a long history to be studied, and satisfy most of the functions required for a next generation nonvolatile memory device, but have difficulties in the fabrication processing of making devices further scaled. Therefore, present technology is limited to realize a higher integration of flash memory devices.
In MRAMs, it is reported that operation characteristics of the device may be deteriorated with the miniaturization (or scaling) of devices, and power consumption of the device is necessarily increased along with the integrated devices while the operation speed of the device is very high.
On the contrary, PRAMs can use chalcogenide metal alloy-based phase change material which has been widely used for optical data storage devices such as CD rewritable (CD-RW), digital versatile disk (DVD), and the like. Further, as the fabrication processing of the phase change memory devices well matches with the fabrication processing for typical silicon-based devices, the phase change memory devices can be implemented with an integration degree equal to or greater than that of DRAM. Of course, there still remains a subject to further reduce consumption power for operation than ever, but seeing the results of technology development for PRAMs, they are recently noted as one of the most important non-volatile memory devices for next generation enabling to replace the existing flash memory devices.
Further, another advantage of the PRAM is to allow a multibit memory device being capable of storing plural memories in addition to 0 or 1 in one single device structure. This is required that the crystal structure of a phase change material is maintained a certain state other than fully crystallized structure or fully amorphous structure, and the state can be given by applying an appropriate electric energy, i.e., supply of a predetermined current. It is reported that a value of an intermediate state other than 0 or 1 can be achieved by applying a predetermined current signal. If such a multibit memory device having the function is realized, it is expected that the PRAM will replace all the markets for flash memory devices limited in integration degrees, and significantly increase the integration degree of memory devices. Accordingly, they are highly expected as non-volatile memory devices for next generation portable digital personal assistants.
However, in order to substantially realize such a multibit phase change memory device, a method quite different from the conventional manufacture method for typical PRAMs must be selected. The reason can be explained as follows.
First, a phase change material used for the multibit phase change memory device must exhibit a linear characteristics depending on applied electrical or thermal energy when it is changed from amorphous structure to crystal structure, or from crystal structure to amorphous structure. If a phase change material not linearly varied in its characteristics is used, peripheral circuits with very complicated structures must be prepared to determine operation conditions during a storage or a reading operation of data in intermediate states to drive a device. However, the phase change material satisfying the characteristics has not be developed up to now, and research examples for the required characteristics have not been reported, either.
Secondly, it has not studied about a method of driving such a multibit phase change memory device, and it is expected to adopt a method of appropriately controlling a pulse-type electrical signal of a predetermined level. In specific, there are examples, such as a method of controlling an amount of the thermal energy actually applied to a phase change material by adjusting the absolute value (magnitude of an applied signal) of a pulse-type electrical signal, and a method of controlling an amount of the thermal energy actually applied to a phase change material by changing the pulse width (applied time) of a pulse-type electrical signal. The methods are closely related with a crystallization rate or amorphization rate of the phase change material, and unless a method of arbitrarily controlling the crystallization rate or amorphization rate if necessary is developed, a driving operation of the device is very difficult to realize.
In consideration of the reasons, it is required to develop a new phase change material, which has not been studied, in order to manufacture a multibit phase change memory device and successfully realize the operation characteristics, and to study and research the material in detail. Therefore, much time is expected to take until verifying stable operations of the multibit phase change memory device, based on the current technology for the devices.

Multibit phase change memory device and method of driving the same

Electronics and Telecommunications Research Institute


A mining machine for excavating coal along a coal front of a seam in which a chain displaces excavating tools along an excavating stretch at a leading side across the coal face and a conveying stretch is provided rearwardly thereof, the stretch terminating in direction reversal stations with wheels at opposite ends of the stretches. A linear drive for at least one of the wheels can extend in a gallery alongside the mined cut. According to the invention, the excavating conveyer bottom is at an angular of 70.degree. to 130.degree. to the bottom of the conveying trough and the shafts of the wheels are inclined to the vertical forwardly and upwardly to include angles of 10.degree. to 45.degree..

Mining machines of the aforedescribed type have been provided heretofore, especially for excavating narrow seams by attacking the coal face in a relatively wide cut which corresponds, for example, to at least a portion of the length of the two stretches. The machine is advanced in the direction of the coal face, i.e. transversely to the two stretches, and the coal is excavated by picks or the like of the tools and the excavated material is displaced along the conveying trough to one or the other end of the machine, e.g. into a gallery, tunnel or the like from which the conveyed material can be carried off.
At least one drive unit can be provided for one of the reversing wheels around which the chain passes and can comprise an electric motor and a transmission. The drive station provides a certain tension at least in the excavating stretch for the chain.
In conventional long-wall mining, socalled walking units are commonly provided such that the supported or propped parts were braced upon those riding on the floor of the cut and the advance of the excavating unit is effected in a step-like manner. The trailing part of the machine is thus drawn along after the leading part has been moved forwardly. The resulting excavation, which ultimately deposits the excavated coal in a gallery alongside the cut, requires step like advance of the leading side of the machines at a rate which will follow the plowing of the coal from the seam so that the plows or tools will not have nonworking passes.
The conveyor operates like a flight conveyor, utilizing the same tools to shift the excavated material which falls into the conveying trough toward the end of the machine and into a gallery.
Machines of this type are known from, for example, DE 35 45 302 C2 and DE 40 04 488 and can have various configurations. They have been found to be largely satisfactory and to provide significant rates of removal of the material, i.e. mined coal per unit time. However, in spite of the success of such machines, it has become desirable to further improve the mining efficiency.
One of the problems with conventional systems appears to be the frictional loss which arises in the conveying and excavating troughs and the work in advancing the excavating part and the drawing of the trailing part of the machine thereafter.
Furthermore, the conventional mining machine must have a fairly large cross section and span a substantial length, all of which have posed problems with respect to stability of the machine. In the conventional systems with such machines, undercutting of the coal itself to allow the coal to then drop into the conveying trough was limited and by and large the tools had to be dimensioned to plow coal from the full thickness or height of the coal seam.

Continuously operating mining machine for simultaneous excavation and conveying of coal

Bochumer Eisenhutte Heintzmann GmbH & Co. KG


A coated abrasive having a backing and an abrasive layer coated on the first major of the backing, wherein a cross-section of the abrasive layer normal to the thickness and at a center point of the thickness has a total cross-sectional area of abrasive agglomerates which is substantially the same as that at a point along the thickness which is 75% of a distance the same as that at a point and the contact side; a coated abrasive article having a bond system with a Knoop hardness number of at least 70; a coated abrasive article comprising abrasive agglomerates in the shape of a truncated four-sided pyramid; a method of making the coated abrasive article; and a method of abrading a hard workpiece using a coated abrasive article.

Abrasive articles comprising abrasive particles are used to abrade and/or finish a wide variety of materials, commonly referred to as workpieces, in a wide variety of applications. These applications range from high pressure, high stock removal of metal forgings to polishing eyeglasses.
Abrasive particles, which can include grains and/or agglomerates, have a wide range of properties which provide for their application in the abrasives industry. The selection of a particular type of abrasive particle generally depends on the physical properties of the particles, the workpiece to be abraded, the surface properties desired to be achieved, the performance properties of the abrasive particles, and the economics of selecting a particular abrasive particle for a specific application.
Aluminum oxide, or alumina, is one of the most popular abrasive particles used in the production of coated abrasives, e.g., sandpaper. Alumina is used for a great many applications, such as paint sanding, metal grinding, and plastic polishing. Silicon carbide, also a popular abrasive, is generally known as a sharper mineral than alumina, and is used mainly in woodworking, paint, and glass grinding applications. Diamond and cubic boron nitride (hereafter "CBN"), commonly called "superabrasives," are especially desirous in abrading very hard workpieces such as hardened steel, ceramic, cast iron, and stone. Diamond is typically the preferred superabrasive for non-ferrous materials, while CBN is typically the preferred superabrasive for ferrous materials like hardened steel. However, superabrasives such as diamond and CBN can cost up to 1000 times more than conventional abrasive particles, i.e., aluminum oxide, silicon carbide. Therefore, it is desirable to utilize the superabrasives their full extent.
As noted above, abrasive particles can be in the form of single grains or agglomerates. Abrasive agglomerates are composite particles of a plurality of single abrasive grains bonded together by a binder. During abrading, the agglomerates typically erode or break down and expel used single abrasive grains to expose new abrasive grains. Agglomerates can be used in abrasive products such as coated abrasives, non-woven abrasives, and abrasive wheels and provide a long useful life and efficient use of the abrasive particles.
U.S. Pat. No. 2,001,911 discloses an abrasive article having a flexible backing and numerous small portions of bonded abrasive material which are adhered to the backing by a layer of flexible and resilient intermediate material. The bonded abrasive material consists of a plurality of abrasive blocks mounted on the backing and separated from each other on their sides by narrow fissures.
U.S. Pat. No. 2,194,472 discloses an abrasive article comprising a backing, which can be flexible, and a coating of abrasive aggregates which are porous, angular, and unflattened and which comprise a plurality of single abrasive grains bound together by a bond system. Preparation of an abrasive article can entail screening the aggregates to provide aggregate particles of a reasonably uniform size.
U.S. Pat. No. 3,986,847 discloses an abrasive article such as a grinding wheel having an abrasive section comprising an abrasive phase and a vitreous bond. The abrasive phase comprises either CBN alone or in combination with a second abrasive grain having a coefficient of thermal expansion substantially the same as the coefficient of thermal expansion of CBN. The vitreous bond is a glassy bond having a coefficient of thermal expansion substantially the same as the coefficient of thermal expansion of CBN.
U.S. Pat. No. 4,256,467 discloses a flexible abrasive article comprising a flexible non-electrically conductive mesh material and a layer of electro-deposited metal, which contains diamond abrasive material embedded therein, adhered directly to and extending through the mesh material so that the mesh material is embedded in the metal layer.
U.S. Pat. No. 4,393,021 discloses a method for the manufacture of granular grit particles in which the individual grits are mixed with a binding medium and a filler to form a pasty mass. The mass can be extruded, heated to harden the mass, and then the hardened product can be broken into granular grit particles, each including several individual grits.
U.S. Pat. No. 4,799,939 discloses an abrasive article comprising erodible agglomerates containing individual abrasive grains disposed in an erodible matrix comprising hollow bodies and a binder. The individual abrasive grains can include aluminum oxide, carbides such as silicon carbide, nitrides such as CBN, diamond, and flint. Although the binder is preferably a synthetic organic binder, natural organic binders and inorganic binders can also be used. The agglomerates are typically irregular in shape but can be formed into spheres, spheroids, ellipsoids, pellets, rods, or other conventional shapes.
U.S. Pat. No. 4,871,376 discloses a coated abrasive comprising a substrate backing, an abrasive material, and a bond system comprising a resinous adhesive, inorganic filler, and a coupling agent. The coupling agent can be selected from the group consisting of silane, titanate, and zirconaluminate coupling agents.
U.S. Pat. No. 5,039,311 discloses an abrasive article comprising an erodible abrasive granule comprising a plurality of first abrasive grains bonded together by a first binder to form an erodible base agglomerate, the base agglomerate at least partially coated with second abrasive grains bonded to the periphery of the base agglomerate by a second binder. The first and second binder, which can be the same or different, can be organic or inorganic and can contain additives such as fillers, grinding aids, plasticizers, wetting agents, and coupling agents. The first and second abrasive grains can be the same or different and can include aluminum oxide, silicon carbide, diamond, flint, CBN, silicon nitride, and combinations thereof. The base agglomerate is typically irregular in shape but can be formed into spheres, spheroids, ellipsoids, pellets, rods, or other conventional forms.
U.S. Pat. No. 5,152,917 discloses a coated abrasive article comprising a backing have at least one major surface and abrasive composites on the at least one major surface. The abrasive composites comprise a plurality of abrasive grains dispersed in a binder, which may also serve to bond the abrasive composites to the backing, and have a predetermined shape, for example, pyramidal.
U.S. Pat. No. 5,201,916 discloses an abrasive particle prepared by introducing a boehmite sol into a mold in which the mold cavities are of a specified shape, removing a sufficient portion of the liquid from the sol to form a precursor of the abrasive particle, removing the precursor from the mold, calcining the removed precursor, and sintering the calcined precursor to form the abrasive particle. The mold cavity has a specified three-dimensional shape and can be a triangle, circle, rectangle, square, or inverse pyramidal, frusto-pyramidal, truncated spherical, truncated spheroidal, conical, and frusto-conical.
U.S. Pat. No. 5,314,513 discloses an abrasive article having a flexible substrate, at least one layer of abrasive grains bonded to the front side of the substrate by a make coat and optionally one or more additional coats, wherein at least one of the coats comprises a maleimide binder.
U.S. Pat No. 5,318,604 discloses an abrasive article comprising abrasive elements dispersed in a binder matrix. The abrasive elements comprise individual particles of abrasive material, substantially all of which are partially embedded in a metal binder.
German Patent No. OS 2941298-A1, published Apr. 23, 1981, teaches coated abrasive articles comprising abrasive conglomerates, which have a rugged and irregular surface, prepared by intensively mixing abrasive mineral grains with glass frit and binder; processing the mixture; pressing, drying, and sintering the material; and then crushing the material to form the conglomerate.
U.S. Pat. No. 5,549,962 discloses precisely shaped particles comprising an organic-based binder and methods for making such particles. The organic-based binder may contain a plurality of abrasive grits dispersed therein.
Although abrasive articles are generally selected based on their physical properties and the desire to maximize abrading and extend the useful life of the abrasive article, particular considerations arise when the industry desires an abrasive article having a long life which can abrade hard materials, such as camshafts and crankshafts, for example, in a camshaft belt grinder as disclosed in U.S. Pat. No. 4,833,834, while conforming to design tolerances including providing a precision ground workpiece.

Coated abrasive article, method for preparing the same, and method of using a coated abrasive article to abrade a hard workpiece

Minnesota Mining and Manfacturing Company


An ultrasonic cleaning tool for cleaning a surface has a transducer and a horn for generating and transmitting vibrations to a surface to be cleaned. Cleaning solution can be supplied to the ultrasonic cleaning tool or the surface to be cleaned, and operation of the ultrasonic cleaning tool can agitate the surface and cleaning solution. The tool can be provided as part of a system for cleaning a surface, and the system can include an extraction cleaner or a cleaning cloth.

Surface cleaning tools can be adapted for cleaning a variety of surfaces, such as for stand-alone cleaning or for coupling with a surface cleaning apparatus. Some examples of surface cleaning apparatuses include a portable or hand-carriable unit, an upright-type unit, a canister-type unit, or a stick-type unit. One exemplary surface cleaning apparatus can be adapted to be hand-carried by a user to a cleaning area. Such a surface cleaning apparatus can be provided with hoses and hand tools adapted for cleaning a variety of surfaces.

Ultrasonic cleaning tool and system for cleaning a surface


A method and device to accurately obtain very small quantity of wear of the order of nanometers of a protective film on the surface of a sliding member. A quantity of wear on the surface of a measurement sample including a base and a coating layer is measured by making a spectrum of the surface elements in a reference sample using a surface-element analysis device which analyzes elements on the surface of a substance from an energy spectrum of charged particles obtained by applying excited ionization radiation on the reference sample equivalent to the measurement and by measuring charged particles generated from the surface of the substance. A step of obtaining signal intensity ratios of plural elements from the spectrum is repeated a plurality of times while the surface of the reference sample is being etched and calibration curves which indicate a distribution of the signal intensity ratios of the plural elements in the reference sample are made. Subsequently, an energy spectrum of charged particles from the surface of the measurement sample is measured, signal intensity ratios of specific elements are calculated and compared with the calibration curves to determine a quantity of wear of the measurement sample.

1. Field of the Invention
The present invention relates to a method and a device, which measure a quantity of wear on a protective film formed on a surface of a sliding member, especially a very small quantity of wear of the order of nanometers in order to improve the wear resistance of a sliding member on which wear is caused by contact with other members.
2. Description of the Related Art
When two or more members such as a bearing, a contact part of a switch, a head and a disk in a hard disk drive, are moving (sliding) under a state that the two or more members are contacting with each other, or are discontinuously contacting with each other, a wear resisting protective film of diamond-like carbon and the like has been formed on the surface of the member in order to prevent damages of the member and an increase in friction resistance, which are caused by wear. In such a case, a method which measures a wear quantity of the protective film has been required for optimized designing of a kind and a thickness of the protective film and for prediction of wear life indicating a period to disappearance of the protective film due to the wear.
The simplest method has been a method in which a prism, a pin, or the like is put into contact with a sliding member having a protective film formed thereon and wear caused by relative motion therebetween in a back and forth manner is observed. Though the quantity of wear may be obtained from the area of the worn part or the displacement of the pin, the quantity of wear of at least less than the order of microns may not be measured by the above method. Also, the above method is not appropriate for measurement of a protective film with a thickness of equal to or less than 10 mm which has been used for the thickness of a hard disk drive and the like, for sliding conditions are largely different from environments, in which the protective film has been really used, to cause problems that an effective hardness of the protective film, or a wear mechanism itself is different from real conditions.
Another method which can be used for measurement of a member which has the same structure and which is worn in the same environments with those of real use is a method using an optical shape evaluation device. In the above method, a quantity of wear is obtained as a change in the shape of a wear surface and the quantity of wear may be obtained with an accuracy of equal to or less than 1 nm when the wear is locally occurred, or when an originally convex place is worn out. However, measurement with a high accuracy cannot be expected when the wear surface is approximately parallel to the original surface, or when individual differences in the irregular shapes on the wear surface are large.
Separately from the above-described measurement method by use of changes in the shape, a method which measures the quantity of wear from the thickness of the protective film after sliding has been considered in the case of a protective film with a thin thickness. When the above method is used, the quantity of wear may be measured with the same accuracy as that of the film-thickness measurement, even when the wear surface is parallel to the original surface, and even if there are some individual differences in the surface shapes. Especially, an X-ray photoelectric spectrum analysis method (XPS) in which the X ray is applied on a sample and photoelectrons are detected, the Auger electron spectroscopy (AES) in which an electron beam is applied on a sample and Auger electrons are detected, and the like may be applied for the above-described measurement of a film thickness of approximately 10 nm.
A method in which a film thickness is obtained by measuring ratios between signals of elements embedded in the film and signals of elements included in the base are measured, and by using a theoretical formula indicating a relation between the above ratios and the film thicknesses has been generally applied for the film-thickness measurement using the X-ray photoelectric spectrum method. Such a formula is usually based on a layer structure with a steep interface and parameters such as a mean free path of photoelectrons depending on materials are required to be obtained beforehand by measuring a reference sample with a known film thickness. Since it is difficult to guarantee accuracy of equal to or less than 1 nm by reasoning that approximation or assumption is included in the above theoretical formula as described above, a reference sample and a measurement sample are not strictly the same, and the like, the above formula is not sufficient for measurement of a very small quantity of wear, that is, a reduced film-thickness.
On the other hand, when a film thickness is measured using the Auger electron spectroscopy, a method in which a film thickness is obtained from the sputter time to an appearance of an element embedded in the film, or to a disappearance of the element embedded in the base after measurement of a depth-direction distribution of the element together with sputter etching has been generally used. A sputter etching rate which is required for conversion of sputter time to a film thickness is obtained by measurement in which a reference sample with a known film thickness is measured beforehand, or by measurement of the depth of a sputter etching part with a stylus-type level sensor. The above method is also unsuitable for wear measurement with high accuracy, for a reference sample and a measurement one are not strictly the same, and fluctuations in the sputter etching rates between measurements of both of the samples are directly reflected on the changes in the film thickness.
As described above, the measurement of very small wear of the order of nanometers has been difficult by conventional methods.

Method and device for measuring quantity of wear