A rotary tool includes a housing, a tool holder, and a wrench assembly. The housing includes an end portion having external threads. The tool holder extends from the end portion and includes a fastening member configured for movement between an unclamped position and a clamped position in which the tool holder can engage a tool. The wrench assembly includes a body portion and a wrench member. The body portion includes (i) a plurality of internal threads configured to meshingly engage the external threads and (ii) an opening through which a portion of the tool holder extends when the internal threads are meshingly engaged to the external threads. The wrench member includes a wrench surface configured to engage the fastening member.

Rotary tools are a favorite instrument of professional craftsmen, handymen, homeowners, and hobbyists. The typical rotary tool is a handheld power tool configured for use with a variety of accessory bits/tools that can be used for cutting, carving, sanding, polishing, and many other applications, referred to collectively as cutting operations. One specific example of a rotary tool is the DREMEL® rotary tool sold by the Robert Bosch Corporation.
Most rotary tools include a collet assembly coupled to the drive shaft of an electric motor. The collet assembly is configurable to couple or to decouple an accessory bit to the drive shaft of the electric motor. The electric motor is operable to rotate the collet assembly and any accessory bit coupled thereto. The accessory bit may be removed and replaced with a different accessory bit when the accessory bit becomes nonfunctional or when the user desires to perform a different cutting operation.
Typically, a collet tool is provided to loosen or tighten the collect assembly. For example, the collet tool may be a wrench that is sized to receive a collet nut of the collet assembly. Frequently, the collet tool is small and easily misplaced. Additionally, the size and shape of some collet tools makes them uncomfortable for some users to grasp.
It would, therefore, be desirable to provide a collet tool that is less likely to be misplaced and that is comfortable for most users to grasp and manipulate.


A labeling function associated with generating one or more semantic concepts is received. The received labeling function is used to automatically annotate an existing dataset with the one or more semantic concepts to generate an annotated noisy dataset. A reference dataset annotated with the one or more semantic concepts is received. A training dataset is prepared including by combining at least a portion of the reference dataset with at least a portion of the annotated noisy dataset. The training dataset is used to train a multi-task machine learning model configured to perform both a decision task to predict a decision result and an explanation task to predict a plurality of semantic concepts for explainability associated with the decision task.

Machine learning (ML) involves the use of algorithms that improve automatically through experience and by the use of data. In ML, a model is built based on sample data, known as training data, in order to make predictions or decisions without being explicitly programmed to do so. ML models are able to learn and adapt by analyzing and drawing inferences from patterns in data. ML has been increasingly used to aid humans in making better and faster decisions in a wide range of areas, such as financial services and healthcare. However, it is difficult for humans to comprehend the rationale behind ML models' predictions, hindering trust in their decision-making. Thus, it would be beneficial to develop techniques directed toward making ML decisions more interpretable for humans.

Weakly supervised multi-task learning for concept-based explainability


A laser scanner with a 2D resonant electrostatic micro-mirror has improved aiming visibility, reduced tilt dependence and improved read range. The laser scanner has a field of view that defines a 3D volume and utilizes a laser beam in a light path that is thin relative to the 3D volume. Physical pixel height is enlarged to aid optical imaging plane alignment. A selective filter centered on the lighting wavelength is placed in the image path. The height of the pixel may be artificially induced to be m*w, where m is the lens magnification and w is the light thickness. Diagonal progressive scanning is used to maximize the frequency values so shock resistance of the mirror is increased.

1. Technical Field
The present invention relates to scanners and bar code readers. More particularly it relates to a laser scanner having 2-D resonant electrostatic micro-mirror that enables projection or acquisition of a discrete image. The present invention also relates to a method of improving aiming visibility, reducing tilt dependence and improving read range of solid state 1D/2D stacked bar code readers.
2. Description of the Related Art
Two primary types of prior art scanners and bar code readers include solid state readers and laser scanners. Solid state bar code readers include CCD (charge coupled device) and CMOS (complimentary metal oxide semiconductor) readers. CCD readers use a row or array of photocells. A line or rectangular areas of a bar code is illuminated by a light source, typically LEDs built into the scanner. A 1D bar code is typically a pattern of light and dark lines of varying width. A 1D bar code does not vary vertically. Information is stored along only 1-dimension, the width, of a 1D bar code. A 1D bar code can be read with a reader having a line of LEDs illuminating a line across the width of the bar code.
There are many types of 2D bar codes. A 2D bar code may use stack bar code symbology, a multi-row code or a matrix symbology. A 2D bar code stores information along the width and height of the bar code. The pattern varies both horizontally and vertically. To read a 2D bar code, the scanner needs to have an array of LEDs illuminating the rectangular area of the 2D bar code.
The photosensors 20 in the CCD scanners reads the bar code illuminated by the light source. CMOS readers also capture light on a grid of small photosensors 20. Prior art solid state bar code scanners rely on a lighting path 22 encompassing the image plane and the 3D volume of view 26.
Because the lighting path must encompass the 3D volume of view, prior art solid state bar code scanners can only "read" what is illuminated. Thus, one disadvantage is that these readers cannot be used with bar codes that are wider or larger than the lighting path.
A CCD scanner does not have to be in direct contact with the surface of the bar code; however, its depth of focus is limited. Thus, another disadvantage is that these prior art scanners cannot be used for far field scanning. CCD scanners suffer from low brightness when used at a far field. Further, there is low photometric coupling efficiency. In other words a portion of the light is not captured by the photosensors 20.
Yet another disadvantage with prior art readers, is that they are tilt dependent when reading high-resolution 1D bar codes and thin row 2D stacked bar codes. In other words, the scanner works significantly better when the light is substantially perpendicular to the bar code. The scanning ability is diminished as the light hits the bar codes from a greater or lesser angle such as occurs when the scanner is tilted.
Laser scanners use a moving light source to illuminate the bar code and a photocell receives the light reflected from the bar code. Oscillating mirror(s) sweep the beam across the bar code. The beam can be swept horizontally to read 1D bar codes or the beam can sweep horizontally and vertically in a raster pattern to read 2D bar codes. Because the light emitted from a laser diverges very little as it travels, laser scanners can be used at far field.
In raster scanning, two mirrors scanning in orthogonal directions or one mirror scanning in two dimensions, and a modulated light source generates a 2-D image on a screen.
In other laser scanners, an optical imaging of a line of pixels or matrix of pixels is swept over the scene by a scanning mirror to image the scene as a whole. Pixels can be diffractive or reflective elements.
In digital light processing (DLP) displays, reflective LCD displays, a matrix of micro-mirrors is imaged as a whole onto the projection display to get a 2 dimensional image. The 2-D array of mirrors are less sensitive to the mirror surface curvature and scan with more uniformity than scanners using a 1-D array or raster-scanned displays. Moreover, the electronic throughput is lower and spatial resolution is better.
In grating light valve displays, a line of pixel is made of a 1-dimensional array of light modulators whose the image is swept over a screen by a scanning mirror to get a 2-dimensional image.
A disadvantage of 1-D or 2-D pixel array displays is that they require successful fabrication of many elements while raster-scanned display requires only one element.
Raster-scanned displays can be made smaller and at less cost than 2-D and 1-D scanned displays, making them more appealing for portable display applications.
Prior art, full electrostatic driven single mirror arrangements with electrodes underneath the mirror provide some degree of linearization. However, these scanners suffer from cross-talk, high voltage driving, and are difficult to package at the wafer level.
Prior art, 2-D gimbals suspended mirror with electrodes in the chip plane have simplified packaging with low pressure cavity at the wafer level, high frequency operation at low power driving, and allow independent excitation of both axis and the doesn't suffer from cross talk. However, these are difficult to manufacture and are fragile. The mirrors have low driving torques. As a result, both axes must be actuated in resonance so the oscillations are nonlinear. High Q factor and manufacturing tolerances make it virtually impossible to drive synchronously both axes at predefined frequencies. Moreover, low oscillation frequency value leads to fragile device because of long suspension hinges.
Existing miniaturized optical scanning for projection displays are expensive and power hungry. The current emerging display technologies target large format displays and do not meet the weight and power requirements of mobile applications. There is a need for durable, lightweight, low-power, inexpensive video displays that can be readily manufactured.

Apparatus for diagonal progressive scanning video and method of improving aiming visibility, reducing tilt dependence and improving read range


Disclosed is a headlamp control system for a vehicle capable of illuminating a location of a user by controlling lighting of the vehicle's headlamps and controlling driving of the headlamps through actuators based on communication with a radio signal transmitter possessed by the user. The headlamp control system can include: headlamps; one or more actuators installed in the headlamps for driving the headlamps upward, downward, left, and right; a plurality of radio signal receivers at two or more locations of the vehicle for receiving a radio signal; a portable radio signal transmitter for transmitting a radio signal to the radio signal receiver; and a controller for determining a position of the radio signal transmitter based on the radio signal and controlling the headlamp and the actuator to irradiated the position of the radio signal transmitter.

(a) Field of the Invention
The present invention relates to a headlamp control system and method for a vehicle, and more particularly, to a headlamp control system and method for a vehicle capable of illuminating a place where a user (driver) is located. In particular, the present system and method illuminate a location of user through a radio signal transmitter that is in connection with actuators which control the lighting of the vehicle's headlamps and controlling the driving (positioning) of the headlamps.
(b) Description of the Related Art
In general, a vehicle includes a lighting system that enables the driver to see objects and road conditions in a driving direction while driving at nighttime and in low lighting conditions, and that notifies other drivers on a road of a driving state of the vehicle.
An adaptive front lighting system (AFLS) has been recently introduced to improve front view recognition for the driver and for oncoming drivers. The adaptive front lighting system is capable of selectively changing widths and lengths of beams of headlamps according to a driving condition of a vehicle, road conditions, environmental conditions, and the like. The adaptive front lighting system further provides uniform emission of the headlamp beams in a front direction of the vehicle.
As such, the adaptive front lighting system enables a driver to more rapidly and accurately recognize obstacles or other problems along the driver's path, for example, by changing a beam pattern (an irradiation direction of the to beam) based on road conditions, as well as a vehicle movement direction when the vehicle rotates as illustrated in FIG. 1.
The adaptive front lighting system senses a steering angle of a steering wheel of the vehicle, a speed of the vehicle, and other driving conditions of the vehicle through a sensor. Based on the information sensed, an actuator is driven to control deflection of irradiation directions of the headlamps upwards, downwards, left, and/or right.
Thus, the adaptive front lighting system includes an actuator for controlling driving of the irradiation directions of the headlamps upward, downward, left, and right.
An adaptive front lighting system is described in Korean Patent Application Laid-Open No. 10-2012-0028661, U.S. Patent Application Publication No. US20110121733, and the like.
However, the adaptive headlamps of such adaptive front lighting systems can only be controlled by the actuator while the vehicle is running.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Headlamp control system and method for a vehicle


The cache control device having the fault-tolerant function includes a cache memory configured to store first data with respect to a specific address read from a main memory, and generate and store a first parity bit corresponding to the first data, a shadow cache memory configured to store second data with respect to the specific address, and generate and store a second parity bit corresponding to the second data, and a fault detector configured to perform a parity check operation on the data of the specific address and the parity bit stored in at least one of the cache memory and the shadow cache memory when receiving a data read request with respect to the specific address from a processor, and transmit the data stored in a non-erroneous memory to the processor according to a result of the parity check operation.

1. Field of the Invention
The present invention relates to a cache control device, and more particularly, to a cache control device having a function preventing a fault of a cache memory due to a soft error.
2. Discussion of Related Art
A cache memory is located between a processor and a main memory of a computer, and a memory operating at a high speed under the control of the processor. The cache memory has a smaller storage capacity than the main memory, and has a higher response speed than the main memory. Accordingly, data stored in the cache memory is accessed more quickly than data stored in the main memory.
A portion of data and instructions stored in the main memory may be stored in the cache memory. For example, the cache memory temporarily stores an instruction and data required by the processor together with, an address.
However, when an error is generated in the cache memory due to external factors and an erroneous instruction is read from the cache memory, the processor performs an operation of an unwanted program, or recognizes as an instruction which does not exist since the instruction read from the cache memory cannot be analyzed. Further, when erroneous data from the cache memory is read, the program generates an erroneous result due to the erroneous data.

Cache control device having fault-tolerant function and method of operating the same

ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE


A hydraulically controlled fan drive system (12) having a method of engagement includes a housing assembly (20) containing a hydraulic fluid (48) and an engaging circuit (36). The engaging circuit (36) includes a pitot tube (152) coupled within the housing assembly (20) that receives at least a portion of the hydraulic fluid (48). An engaging circuit (36) engages the housing assembly (20) to a fan shaft (44) in response to supply of the hydraulic fluid (48) from the pitot tube (152). An electrical control circuit (40) having a relief valve assembly (225) coupled to a main controller (176) is used to control the fluid pressure within the pitot tube (152) that controls the engagement of the housing assembly (20).

The present invention relates to friction coupling devices and fluid coupling devices, such as friction clutch assemblies and viscous drives; the fluid coupling devices being of the type that include both a fluid operating chamber and a fluid reservoir chamber, and valving to control the quantity of fluid in the operating chamber.
Although the present invention may be used advantageously in various configurations and applications, it is especially advantageous in a coupling device of the type used to drive a radiator cooling fan of an internal combustion engine for a over the road truck, such as a class 8 truck, and will be described in connection therewith.
Friction coupling devices and fluid coupling devices that drive radiator cooling fans are generally of two types, dry friction clutch assemblies and viscous drives, respectively.
Dry friction clutch assemblies tend to have two operating conditions "ON and OFF" referring to when a friction clutch is either fully engaged or fully disengaged. When a friction clutch assembly is providing cooling the clutch is fully engaged and not slipping. When the friction clutch assembly is not providing cooling the assembly is fully disengaged and slip speed is at a maximum between a clutch plate and an engagement surface.
The dry friction clutch assemblies generally have low thermal capacity, since they typically do not incorporate fluid flow cooling mechanisms. Thus, the clutch assemblies have minimal cooling capability and are unable to cycle repeat in short durations of time. Also, because of low thermal capacity, the clutch assemblies are also limited in torsional capacity, such that they are incapable of engaging at high engine revolutions per minute (rpm) or high engine speeds. The thermal energy that is generated during engagement at high engine rpm speeds can "burn up" or cause the clutch assembly to become inoperative.
Viscous drives, on the other hand, have become popular due to their ability to cycle repeat, engage at higher engine speeds, and have varying degrees of engagement. Viscous drives have an operating range of engagement and are generally less engaged at higher engine speeds and generally more engaged at lower engine speeds. Viscous drives are never fully engaged for internal viscous shear purposes.
Unfortunately, viscous drives are also thermally and torsionally limited. Viscous drives are always slipping to some degree causing them to be incapable of turning at fully engaged peak operating speeds or at higher speeds than originally designed. Since viscous drives are continuously slipping, they are continuously generating heat, unlike friction clutch assemblies. Viscous drives are further limited in that the more engine cooling needed the larger and more costly the viscous drive and cooling fan that is required. Thus, for increased engine cooling requirements viscous drives can become impractical in size and cost.
Due to increased engine cooling requirements, a current desire exists for a fan drive system that is capable of not only providing an increased amount of cooling over traditional fan drive systems but also that it have the associated advantages of a friction clutch assembly and of a viscous drive, as stated above, without the associated disadvantages. It is also desirable that the fan drive system be practical and reasonable in size and cost, so as to be approximately similar to and preferably not to exceed that of traditional fan drive systems.

Fan drive having pressure control (fluid) of a wet friction fan drive


Debris removal apparatus, systems, and methods of using the same are described. An example debris removal apparatus includes a shaft, an energy source, a motor, a fan attached to the motor, and a switch. The shaft has a lengthwise axis, a first end, a second end, a first portion, a second portion, a third portion and defines an opening on the second end, a passageway in fluid communication with the opening, and a plurality of inlet openings on the third portion of the shaft in fluid communication with the passageway. The motor is operatively connected to the energy source and disposed between the plurality of inlet openings and the second end of the shaft. The motor has a lengthwise axis extending through a drive shaft. The lengthwise axis of the motor is parallel to the lengthwise axis of the shaft. The switch is operatively connected to the motor.

Debris removal apparatus, such as leaf blowers, are common tools used by homeowners and lawn care companies to move a variety of debris across grass and other surfaces. Current debris removal apparatus, however, have several significant drawbacks. For example, they are bulky, heavy, noisy, and most require use of a gas engine. Furthermore, some apparatus position the motor in a handle, or adjacent the user, such that the motor is located at an end opposite to where air flows out of the apparatus, which significantly reduces the efficiency of the motor and reduces airflow. Various developments have been made in an effort to address the drawbacks of current apparatus. However, these developments have failed to produce an apparatus that is convenient to use in quick application settings (e.g., cleaning stairs, removing light snow from automobile, removing sand and tree debris from golf putting surfaces, starting small fires) and that doesn't require a user to bend over to direct airflow on the surface intended to be cleaned.
Therefore, a need exists for new and useful debris removal apparatus, systems, and of methods of using the same.


According to one embodiment of the invention, a method is provided for receiving a timestamp from a caller via a telephone connection; receiving a device identifier from the caller, in which the device identifier identifies a device; determining a cryptographic key based on the device identifier; determining an indication of a time based on the timestamp and the cryptographic key; providing the indication of the time to the caller; determining an account; and charging a fee to the account.

1. Field of the Invention
The present invention relates generally to methods and apparatuses for document timestamping. More particularly, the invention relates to secure and authenticable timestamping of documents in such a way that the timestamp can be verified by a party who was not necessarily present during the timestamping.
2. Background
In many instances where timestamped documents are to be communicated to a temporally or spatially distant recipient, one would like to be able to verify the authenticity and integrity of the timestamp. For example, consider the problem of proving document creation in the course of business transactions. Both the author and the recipient would like to be able to timestamp the document in a manner that demonstrates to others that it was stamped: 1) by the timestamping device (i.e., knowing which device generated the timestamp), and 2) at the indicated time (i.e., that the timestamp has not been modified during or subsequent to timestamping). The first requirement relates to timestamping device authenticability, while the second requirement relates to time integrity. Either or both of these requirements may exist anytime documents are created by one party (or at one location) not under the direct control of the recipient. Common examples include timestamps at the top of fax pages, timestamps at the bottoms of printouts, and postage marks as evidence of mailing. Besides documents, other examples include timeclocks for hourly employees, or for parking garage patrons, for recording the date/time of entry onto the premises.
As indicated by the above examples, many timestamping applications are associated primarily with physical (e.g., paper-based) applications rather than electronic (e.g., digital) applications. This is especially true for document generation where, despite the almost universal use of computer word processing, the majority of documents are still used and stored on paper because of its advantages over electronic media. Such advantages include: 1) ease of document creation (e.g., taking handwritten notes), 2) ease of document retrieval (e.g., without computers or other specialized document readers and no worries about evolving diskette or word processing file formats), 3) long-term stability of paper (e.g., degradation of magnetic media), 4) low cost, and 5) portability. Therefore, a timestamping device for everyday usage should be particularly suitable for use with paper-based documents.
Traditionally, timestamping devices have relied on mechanical inaccessibility, fixed location, and public display to suggest the accuracy of timestamps produced thereby. Many contemporary electronic timestamping devices provide even less assurance than mechanical devices because their timestamping mechanisms are user-accessible, user-resettable, and hidden from public view. Examples include camera date recorders to timestamp pictures, answering machine/voicemail date/time recorders, and computer clocks to timestamp file creation and output such timestamps on document trailers.
Whether mechanical or electronic, each of the above-mentioned examples is prone to resetting of the clock prior to timestamping, or modification of the timestamp after timestamping. For example, the ability to reset the internal date/time is built into almost all personal computer operating systems. Furthermore, the purely electronic devices are especially prone to tampering because of the ease with which a purely electronic document to be timestamped can be accessed and manipulated. Such ease of manipulation has led to the creation of devices which cryptographically certify the authenticity and integrity of electronic documents. Examples of such devices may be seen in several US patents (U.S. Pat. Nos. 5,189,700; 5,157,726; 5,136,647; 5,136,646; 5,022,080; 5,001,752; and 4,786,940) disclosing devices that input digital data, cryptographically certify the digital data, and output a digital message. In addition, certain of these devices optionally add time from a secure internal clock to the digital message.
The aforementioned devices are directed at applications whose primary goal is digital data certification, and any associated timestamping is an adjunct to that goal. In contrast, in many document timestamping applications, the primary goal is time certification rather than data certification. Although the data certification devices can be used for timestamping, such usage would be relatively complicated, expensive, and ill-suited for paper-based timestamping applications because the document data must be digitized. For example, the use of data certification devices with paper documents would require the addition of a document scanner to generate a digital representation of the document for input to the device, leading to increased device cost and complexity.
Furthermore, because data representing the document would be included in the cryptographic message, one wishing to verify the message (e.g., by recomputing the timestamp) would also have to create a digital representation of the message—a costly and possibly infeasible operation for those with limited capabilities. It is often inefficient to timestamp a paper document such that verification of the timestamp requires the timestamp recipient to re-digitize the paper document.
Therefore, there exists a need for a simple, inexpensive, easy-to-use device that generates an accurate and unalterable timestamp, for application to physical media such as paper documents, that can be easily verified by the document recipient.

This patent is subject to a terminal disclaimer.

Method and apparatus for verifying secure document timestamping


Novel cannabimimetic pyrazole derivatives are presented which have preferentially high affinities for both of the cannabinoid CB1 or CB2 receptor sites. The improved receptor affinity makes these analogs useful as experimental tools for cannabinoid receptor studies as well as clinically useful agents in individuals and animals for treatment of memory deficits associated with aging or neurological diseases, as anti-obesity agents, as medications for schizophrenia and treatment of septic shock syndrome.

Classical cannabinoids such as the marijuana derived cannabinoid Δ9-tetrahydrocannabinol (Δ9-THC), as well as endogenous ligands (anandamide) produce their pharmacological effects via their agonist properties at specific cannabinoid receptors in the body. So far, two cannabinoid receptors have been characterized: CB1, a central receptor found in the mammalian brain and peripheral tissues and CB2, a peripheral receptor found only in the peripheral tissues. Compounds that are agonists or antagonists for one or both of these receptors have been shown to provide a variety of pharmacological effects. See, for example, Pertwee, R.G., Pharmacology of cannabinoid CB1 and CB2 receptors, Pharmacol. Ther., (1997) 74:129-180 and Di Marzo, V., Melck, D., Bisogno, T., DePetrocellis, L., Endocannabinoids: endogenous cannabinoid receptor ligands with neuromodulatory action, Trends Neurosci. (1998) 21:521-528.
Over the last few years, a number of potent synthetic cannabinoid agonists have been developed. These agonist materials have helped in the characterization of cannabinoid receptors and with studies of receptor molecular properties.
Cannabinoid antagonists are compounds that bind to one of the CB1 or CB2 receptors but have no effect. There is considerable interest in developing cannabinoid antagonists possessing high affinity for one of the CB1 or CB2 receptors. Such cannabinoid antagonist materials provide a tool to better understand the mechanisms by which cannabinoid agonists produce their pharmacological effects and for the development of new therapeutic agents.
One class of cannabimimetic antagonists encompasses pyrazole derivatives. Pyrazole analogs have been found to act as antagonists for the CB1 and CB2 receptors, and occasionally to act as agonists for the CB1 and CB2 receptors. Most of the known materials show high receptor affinity for only the CB1 cannabinoid receptor. See for instance, Barth, F. et al, Pyrazole Derivatives, Method Of Preparing Them And Pharmaceutical Compositions In Which They Are Present; U.S. Pat. No. 5,624,941 to Barth et al, issued Apr. 29, 1997; Rinaldi-Carmona, M. et al, SR141716A, A Potent And Selective Antagonist Of The Brain Cannabinoid Receptor, FEBS Lett. 1994, 350, 240-244; Rinaldi-Carmona, M. et al, Biochemical And Pharmacological Characterization Of SR14171 6A, The First Potent And Selective Brain Cannabinoid Receptor Antagonist, Life Sci. 1995, 56, 1941-1947; and Makriyannis, A., Structure-Activity Relationships Of Pyrazole Derivatives As Cannabinoid Receptor Antagonists, J. Med. Chem. 42, 769-776, 1999.

Pyrazole derivatives as cannabinoid receptor antagonists


A heddle frame includes a top rail and a bottom rail connected at their ends with end members to form a rectangular frame. An adjustable center brace assembly extends between the top and bottom rails, and includes an elongated brace extending through the top rail with a bottom end adjustably and lockingly engaged with the bottom rail. The brace may have a multi-sided head at the top thereof configured to be engaged by a conventional driving tool. A locking block is disposed over the multi-sided head and is a removably attached to the top rail. The locking block has a recess defined in the underside thereof with a width corresponding generally to that of the multi-sided head for rotationally locking the head and center brace. The head of the brace has a width so as not to extend beyond the sides of the top rail, and the head can be rotated with a conventional driving device without removal of the heddle frame from the textile machine, or interfering with adjacent heddle frames.

The present invention relates to a heddle frame for a loom, and in particular to an improved heddle frame having a center brace for maintaining parallelism between the top and bottom rails of the heddle frame.
A known heddle frame with an improved center brace assembly is disclosed in U.S. Pat. No. 4,924,916. In this patent, the heddle frame comprises top and bottom rails which are typically made of extruded aluminum, as commonly understood in the art. The top and bottom rails are connected to each other at their ends by end struts or members to provide a rigid connection between the rails and to define a generally rectangular harness or heddle frame. The frame includes top and bottom heddle supporting rods or rails upon which the heddles are slidably mounted, as is commonly understood in the art. A center brace is mounted midway between the ends of the frame, and in some cases a plurality of braces may be employed. The center brace serves to prevent distortion of the frame and to maintain the parallel relationship between the top and bottom rails.
In the '916 patent, the center brace extends through an opening into the top rail and into an opening in the bottom rail. A top sleeve is disposed in an opening in the top rail and extends about the center brace to separate the brace from the opening in the top rail. Likewise, a bottom sleeve is disposed on the bottom rail and is threaded onto the center brace. Means are provided on the upper surface of the top rail to secure and retain the center brace within the opening.
U.S. Pat. No. 5,630,448 describes an embodiment of a heddle frame having a center brace assembly wherein the center brace extends between the top rail and the bottom rail. First and second locking blocks are attached to the top rail and the bottom rail and are configured to respectively receive a first flange at one end of the center brace and a second flange at the opposite end of the center brace, and to exert forces on the first and second flanges to create opposing torques thereon. This generates a torque on the center brace and thus locks the first flange and the second flange within their respective locking blocks.
U.S. Pat. No. 2,909,199 describes an early embodiment of a heddle frame incorporating a center brace assembly wherein the center brace or rod is threaded to a head piece. The head piece is seated in a recess of a member bolted to the top rail. A locking member is superposed on this recessed member. The locking member has a recess on its underside in which the head piece is positioned whereby rotation of the rod or center brace is prevented when the locking member is in its operative position.
One drawback with the known center brace assemblies is that the adjusting mechanism extends laterally beyond the width of the heddle frames and thus interferes with adjacent heddle frames. Thus, adjustment of one heddle frame is impeded by and may actually cause misalignment of adjacent heddle frames, and so forth.
The present invention provides an improved center brace assembly for heddle frames that can be vertically adjusted without interfering with adjacent heddle frames.

Heddle frame with adjustable center brace assembly


A process for the production of polypropylene comprising continuously contacting liquid propylene or a mixture comprising liquid propylene and one or more other alpha-olefins in one or more reaction zones, under gas phase polymerization conditions, with a catalyst system comprising (i) a solid particulate catalyst precursor, which includes magnesium; titanium; a halogen which is chlorine, bromine, or iodine, or mixtures thereof; and, as an inside electron donor, a carboxylic acid ester; (ii) a hydrocarbylaluminum cocatalyst; and (iii) as an outside electron donor, a silicon compound containing at least one silicon-oxygen-carbon linkage, the particles of precursor being carried into the reaction zone(s) via a portion of the liquid propylene, the flow rate of said portion having a Reynolds number greater than about 15,000.

In U.S. Pat. No. 5,093,415, a process is provided for producing stereoregular polymers. More particularly, it was found that polymers having an isotactic index of at least 96 percent could be prepared in high yield at high production rates by polymerizing an alpha-olefin in a low pressure gas phase fluidized bed process at temperatures in excess of 50.degree. C. employing a catalyst system comprising (i) a solid catalyst precursor, which includes magnesium, titanium, halogen, and an inside electron donor, i.e., a polycarboxylic acid ester containing two coplanar ester groups attached to adjacent carbon atoms; (ii) a hydrocarbylaluminum cocatalyst; and (iii) an outside electron donor or selectivity control agent, i.e., a silicon compound containing a silicon-oxygen-carbon linkage wherein the atomic ratio of aluminum to silicon is in the range of about 0.5:1 to about 100:1 and the atomic ratio of aluminum to titanium is in the range of about 5:1 to about 300:1.
This catalyst system can be used to provide homopolymers of propylene and copolymers of propylene and one or more alpha-olefins. The high activity at temperatures in the range of about 50.degree. C. to about 110.degree. C. makes this catalyst system very attractive; however, it is also desired to control average particle size within prescribed limits while maintaining high bulk density. Homopolymers can generate excessive fines raising the concern of a possible dust explosion. Random copolymers can become too large presenting the problems of poor flowability and low bulk density. Fines, flowability, and bulk density are dependent on average particle size, which is in turn dependent on resin morphology.

Process for the production of polypropylene

Union Carbide Chemicals & Plastics Technology Corporation


The present invention relates to novel benzazepinone derivatives, their synthesis, and their use as αv integrin receptor antagonists. More particularly, the compounds of the present invention are antagonists of the integrin receptors αvβ3 and αvβ5 and are therefore useful for inhibiting bone resorption, treating and/or preventing osteoporosis, and inhibiting vascular restenosis, diabetic retinopathy, macular degeneration, angiogenesis, atherosclerosis, inflammatory arthritis, cancer, and metastatic tumor growth.

It is believed that a wide variety of disease states and conditions can be mediated by acting on integrin receptors and that integrin receptor antagonists represent a useful class of drugs. Integrin receptors are heterodimeric transmembrane receptors through which cells attach and communicate with extracellular matrices and other cells. (See S. B. Rodan and G. A. Rodan, "Integrin Function In Osteoclasts," Journal of Endocrinology, 154: S47–S56 (1997), which is incorporated by reference herein in its entirety).
In one aspect of the present invention, the compounds disclosed herein are useful for inhibiting bone resorption. Bone resorption is mediated by the action of cells known as osteoclasts. Osteoclasts are large multinucleated cells of up to about 400 mm in diameter that resorb mineralized tissue, chiefly calcium carbonate and calcium phosphate, in vertebrates. Osteoclasts are actively motile cells that migrate along the surface of bone, and can bind to bone, secrete necessary acids and proteases, thereby causing the actual resorption of mineralized tissue from the bone. More specifically, osteoclasts are believed to exist in at least two physiological states, namely, the secretory state and the migratory or motile state. In the secretory state, osteoclasts are flat, attach to the bone matrix via a tight attachment zone (sealing zone), become highly polarized, form a ruffled border, and secrete lysosomal enzymes and protons to resorb bone. The adhesion of osteoclasts to bone surfaces is an important initial step in bone resorption. In the migratory or motile state, the osteoclasts migrate across bone matrix and do not take part in resorption until they again attach to bone.
Integrins are involved in osteoclast attachment, activation and migration. The most abundant integrin on osteoclasts, e.g., on rat, chicken, mouse and human osteoclasts, is an integrin receptor known as αvβ3, which is thought to interact in bone with matrix proteins that contain the RGD sequence. Antibodies to αvβ3 block bone resorption in vitro indicating that this integrin plays a key role in the resorptive process. There is increasing evidence to suggest that αvβ3 ligands can be used effectively to inhibit osteoclast mediated bone resorption in vivo in mammals.
The current major bone diseases of public concern are osteoporosis, hypercalcemia of malignancy, osteopenia due to bone metastases, periodontal disease, hyperparathyroidism, periarticular erosions in rheumatoid arthritis, Paget's disease, immobilization-induced osteopenia, and glucocorticoid-induced osteoporosis. All of these conditions are characterized by bone loss, resulting from an imbalance between bone resorption, i.e. breakdown, and bone formation, which continues throughout life at the rate of about 14% per year on the average. However, the rate of bone turnover differs from site to site; for example, it is higher in the trabecular bone of the vertebrae and the alveolar bone in the jaws than in the cortices of the long bones. The potential for bone loss is directly related to turnover and can amount to over 5% per year in vertebrae immediately following menopause, a condition which leads to increased fracture risk.
In the United States, there are currently about 20 million people with detectable fractures of the vertebrae due to osteoporosis. In addition, there are about 250,000 hip fractures per year attributed to osteoporosis. This clinical situation is associated with a 12% mortality rate within the first two years, while 30% of the patients require nursing home care after the fracture.
Individuals suffering from all the conditions listed above would benefit from treatment with agents which inhibit bone resorption.
Additionally, αvβ3 ligands have been found to be useful in treating and/or inhibiting restenosis (i.e. recurrence of stenosis after corrective surgery on the heart valve), atherosclerosis, diabetic retinopathy, macular degeneration, and angiogenesis (i.e. formation of new blood vessels), and inhibiting viral disease. Moreover, it has been postulated that the growth of tumors depends on an adequate blood supply, which in turn is dependent on the growth of new vessels into the tumor; thus, inhibition of angiogenesis can cause tumor regression in animal models (See Harrison's Principles of Internal Medicine, 12th ed., 1991, which is incorporated by reference herein in its entirety). Therefore, αvβ3 antagonists which inhibit angiogenesis can be useful in the treatment of cancer by inhibiting tumor growth (See, e.g., Brooks et al., Cell, 79:1157–1164 (1994), which is incorporated by reference herein in its entirety).
Evidence has also been presented suggesting that angiogenesis is a central factor in the initiation and persistence of arthritic disease, and that the vascular integrin αvβ3 may be a preferred target in inflammatory arthritis. Therefore, αvβ3 antagonists which inhibit angiogenesis may represent a novel therapeutic approach to the treatment of arthritic disease, such as rheumatoid arthritis (see C. M. Storgard, et al., "Decreased angiogenesis and arthritic disease in rabbits treated with an αvβ3 antagonist," J. Clin. Invest., 103: 47–54 (1999); "Cilengitide," Drugs of the Future, 25: 674–678 (2000); and A. M. Badger, et al., "Disease-Modifying Activity of SB 273005, An Orally Active, Nonpeptide αvβ3 (Vitronectin Receptor) Antagonist, in Rat Adjuvant-Induced Arthritis," Arthritis & Rheumatism, 44: 128–137 (2001); each of which is incorporated by reference herein in its entirety).
Moreover, the compounds of this invention can also inhibit neovascularization by acting as an antagonist of the integrin receptor αvβ5. A monoclonal antibody for αvβ5 has been shown to inhibit VEGF-induced angiogenesis in rabbit cornea and the chick chorioallantoic membrane model (See M. C. Friedlander, et al., Science 270: 1500–1502 (1995), which is incorporated by reference herein in its entirety). Thus, compounds that antagonize αvβ5 are useful for treating and preventing macular degeneration, diabetic retinopathy, cancer, and metastatic tumor growth.
Additionally, the compounds of the instant invention can inhibit angiogenesis and inflammation by acting as antagonists of αv integrin receptors associated with other β subunits, suh as αvβ6 and αvβ8 (See, for example, Melpo Christofidou-Solomidou, et al., "Expression and Function of Endothelial Cell αv Integrin Receptors in Wound-Induced Human Angiogenesis in Human Skin/SCID Mice Chimeras," American Journal of Pathology, 151: 975–83 (1997) and Xiao-Zhu Huang, et al., "Inactivation of the Integrin β6 Subunit Gene Reveals a Role of Epithelial Integrins in Regulating Inflammation in the Lungs and Skin," Journal of Cell Biology, 133: 921–28 (1996), which are incorporated by reference herein in their entirety).
In addition, the compounds of this invention can also antagonize both the αvβ3 and αvβ5 receptors and is therefore useful for inhibiting bone resorption, treating and preventing osteoporosis, and inhibiting vascular restenosis, diabetic retinopathy, macular degeneration, angiogenesis, atherosclerosis, inflammatory arthritis, cancer, and metastatic tumor growth.
Peptidyl as well as peptidomimetic antagonists of the αvβ3 integrin receptor have been described both in the scientific and patent literature. For example, reference is made to W. J. Hoekstra and B. L. Poulter, Curr. Med. Chem. 5: 195–204 (1998) and references cited therein; WO 95/32710; WO 95/37655; WO 97/01540; WO 97/37655; WO 98/08840; WO 98/18460; WO 98/18461; WO 98/25892; WO 98/31359; WO 98/30542; WO 99/15506; WO 99/15507; WO 00/03973; EP 853084; EP 854140; EP 854145; U.S. Pat. Nos. 5,204,350; 5,217,994; 5,639,754; 5,741,796; 5,780,426; 5,929,120; 5,952,341; 6,017,925; and 6,048,861. Evidence of the ability of αvβ3 integrin receptor antagonists to prevent bone resorption in vitro and in vivo has been presented (see V. W. Engleman et al., "A Peptidomimetic Antagonist of the αvβ3 Integrin Inhibits Bone Resorption In Vitro and Prevents Osteoporosis In Vivo," J. Clin. Invest. 99: 2284–2292 (1997); S. B. Rodan et al., "A High Affinity Non-Peptide αvβ3 Ligand Inhibits Osteoclast Activity In Vitro and In Vivo," J. Bone Miner. Res. 11: S289 (1996); J. F. Gourvest et al., "Prevention of OVX-Induced Bone Loss With a Non-peptidic Ligand of the αvβ3 Vitronectin Receptor," Bone 23: S612 (1998); M. W. Lark et al., "An Orally Active Vitronectin Receptor αvβ3 Antagonist Prevents Bone Resorption In Vitro and In Vivo in the Ovariectomized Rat," Bone 23: S219 (1998)).
The αvβ3 integrin receptor recognizes the Arg-Gly-Asp (RGD) tripeptide sequence in its cognate matrix and cell surface glycoproteins (see J. Samanen, et al., "Vascular Indications for Integrin αv Antagonists," Curr. Pharmaceut. Design 3: 545–584 (1997)). A benzazepine nucleus has been employed among others by Genentech and SmithKline Beecham as a conformationally constrained Gly-Asp mimetic to elaborate nonpeptide αvβ3 integrin receptor antagonists substituted at the N-terminus with heterocyclic arginine mimetics (see R. M. Keenan et al., "Discovery of Potent Nonpeptide Vitronectin Receptor (αvβ3) Antagonists," J. Med. Chem. 40: 2289–2292 (1997); R. M. Keenan et al., "Benzimidazole Derivatives As Arginine Mimetics in 1,4-Benzodiazepine Nonpeptide Vitronectin Receptor (αvβ3) Antagonists," Bioorg. Med. Chem. Lett. 8: 3165–3170 (1998); and R. M. Keenan et al., "Discovery of an Imidazopyridine-Containing 1,4-Benzodiazepine Nonpeptide Vitronectin Receptor (αvβ3) Antagonist With Efficacy in a Restenosis Model," Bioorg. Med. Chem. Lett. 8: 3171–3176 (1998). Patents assigned to SmithKline Beecham that disclose such benzazepine, as well as related benzodiazepine and benzocycloheptene, αvβ3 integrin receptor antagonists include WO 96/00574, WO 96/00730, WO 96/06087, WO 96/26190, WO 97/24119, WO 97/24122, WO 97/24124, WO 98/14192, WO 98/15278, WO 99/05107, WO 99/06049, WO 99/15170, WO 99/15178, WO 99/15506, and U.S. Pat. No. 6,159,964, and to Genentech include WO 97/34865. The dibenzocycloheptene, dibenzocycloheptane and dibenzoxazepine scaffolds have also been employed as a Gly-Asp mimetic to afford αvβ3 antagonists (see WO 97/01540, WO 98/30542, WO 99/11626, WO 99/15508, WO 00/33838, U.S. Pat. Nos. 6,008,213, and 6,069,158, all assigned to SmithKline Beecham).
Other integrin receptor antagonists incorporating backbone conformational ring constraints have been described in the patent literature. Published patent applications or issued patents disclosing antagonists having a phenyl constraint include WO 98/00395, WO 99/32457, WO 99/37621, WO 99/44994, WO 99/45927, WO 99/52872, WO 99/52879, WO 99/52896, WO 00/06169, EP 0 820,988, EP 0 820,991, U.S. Pat. Nos. 5,741,796; 5,773,644; 5,773,646; 5,843,906; 5,852,210; 5,929,120; 5,952,381; 6,028,223; and 6,040,311. Published patent applications or issued patents disclosing antagonists having a monocyclic ring constraint include WO 99/26945, WO 99/30709, WO 99/30713, WO 99/31099, WO 99/59992, WO 00/00486, WO 00/09503, EP 0 796,855, EP 0 928,790, EP 0 928,793, U.S. Pat. Nos. 5,710,159; 5,723,480; 5,981,546; 6,017,926; and 6,066,648. Published patent applications or issued patents disclosing antagonists having a bicyclic ring constraint include WO 98/23608, WO 98/35949, WO 99/33798, EP 0 853,084, U.S. Pat. Nos. 5,760,028; 5,919,792; and 5,925,655.
Reference is also made to the following reviews for additional scientific and patent literature that concern alpha v integrin antagonists: M. E. Duggan, et al., "Ligands to the integrin receptor αvβ3, Exp. Opin. Ther. Patents, 10: 1367–1383 (2000); M. Gowen, et al., "Emerging therapies for osteoporosis," Emerging Drugs, 5: 1–43 (2000); J. S. Kerr, et al., "Small molecule αv integrin antagonists: novel anticancer agents," Exp. Opin. Invest. Drugs, 9: 1271–1291 (2000); and W. H. Miller, et al., "Identification and in vivo efficacy of small-molecule antagonists of integrin αvβ3 (the vitronectin receptor)," Drug Discovery Today, 5: 397–408 (2000).
However, there still remains a need for small-molecule, non-peptidic selective αv integrin receptor antagonists that display improved potency, pharmacodynamic, and pharmacokinetic properties, such as oral bioavailability and duration of action, over already described compounds. Such compounds would provide an enhancement in the treatment, prevention, or suppression of various pathologies enumerated above that are mediated by αv integrin receptor binding and cell adhesion and activation.
In WO 00/48603 (Aug. 24, 2000) and WO 00/46215 (Aug. 10, 2000), we disclosed a series of dibenzazepine and benzazepine derivatives, respectively, which are αv integrin receptor antagonists. In the present invention, we describe novel benzazepinone derivatives with potent αv integrin receptor antagonistic properties.
It is therefore an object of the present invention to provide novel benzazepinone derivatives, which are useful as αv integrin receptor antagonists.
It is another object of the present invention to provide novel benzazepinone derivatives which are useful as αvβ3 receptor antagonists.
It is another object of the present invention to provide novel benzazepinone derivatives which are useful as αvβ5 receptor antagonists.
It is another object of the present invention to provide novel benzazepinone derivatives which are useful as dual αvβ3/αvβ5 receptor antagonists.
It is another object of the present invention to provide pharmaceutical compositions comprising the αv integrin receptor antagonists.
It is another object of the present invention to provide methods for making the pharmaceutical compositions of the present invention.
It is another object of the present invention to provide methods for eliciting an αv integrin receptor antagonizing effect in a mammal in need thereof by administering the compounds and pharmaceutical compositions containing the compounds of the present invention.
It is another object of the present invention to provide compounds and pharmaceutical compositions containing the compounds useful for inhibiting bone resorption, restenosis, atherosclerosis, inflammatory arthritis, diabetic retinopathy, macular degeneration, angiogenesis, cancer, and metastatic tumor growth.
It is another object of the present invention to provide compounds and pharmaceutical compositions containing the compounds useful for treating osteoporosis.
It is another object of the present invention to provide methods for inhibiting bone resorption, restenosis, atherosclerosis, inflammatory arthritis, diabetic retinopathy, macular degeneration, angiogenesis, cancer, and metastatic tumor growth.
It is another object of the present invention to provide methods for treating osteoporosis.
These and other objects will become readily apparent from the detailed description which follows.

Benzazepinone alpha vintegrin receptor antagonists


A vehicle includes an engine that generates drive torque and a power transfer device that selectively transfers the drive torque to a driveline. The power transfer device includes an input shaft, an output shaft and a torque biasing system. The torque biasing system has a clutch pack and an actuator that regulates engagement of the clutch pack. An on-demand lubrication system supplies a lubricating fluid flow through the clutch pack based on a control signal generated by a control system. A passively actuated positive displacement pump supplies the lubricating fluid flow through the clutch pack based on a speed differential between the input shaft and the output shaft.

Power transfer systems of the type used in motor vehicles such as, for example, four-wheel drive transfer cases, an all-wheel drive power take-off units (PTU) and axle drive modules are commonly equipped with a torque transfer mechanism. Torque transfer mechanisms are operable to regulate the transfer of drive torque from a rotary input component to a rotary output component. Typically, a friction clutch is operably disposed between the input and output components. Engagement of the friction clutch is varied to regulate the amount of drive torque transferred from the input component to the output component.
The degree of clutch engagement is a function of the clutch engagement force that is applied to the friction clutch via a clutch actuator system. Traditional clutch actuator systems include a drive mechanism and a clutch operator mechanism. The clutch operator mechanism converts the force or torque generated by the drive mechanism into the clutch engagement force which is then applied to the friction clutch. The drive mechanism can be passively-actuated or, in the alternative, be a power-driven device which is controlled based on a control signal generated by a control system.
The quality and accuracy of drive torque transfer across the friction clutch is largely based on the frictional interface between the interleaved clutch plates. When partially engaged, the clutch plates slip relative to one another, thereby generating heat. As is known, lubricating fluid is routed to flow through the clutch pack to cool the clutch plates. In a typical clutch engagement cycle, the heat generated due to the frictional work is absorbed by the friction plates as well as via convection due to oil flow through the clutch plates. Excessive heat generation, however, can degrade the lubricating fluid as well as damage the clutch plates.
Additionally, traction control systems require the clutch actuator system to respond to torque commands in a quick and accurate manner. The ability to accurately meet the torque request is largely dependent on the coefficient of friction of the clutch plates. However, it has been demonstrated that this coefficient can change quite rapidly under various loading and/or slip conditions. Specifically, the coefficient tends to fade due to significant temperature increases in the clutch plates which results from insufficient heat removal. It has, however, been demonstrated that improvements in the flow of oil to the friction clutch can improve the stability of the friction coefficient. Specifically, the lube flow rate across the friction clutch has a significant impact on stability of the friction coefficient, particularly during continuous slip conditions. Furthermore, it has been demonstrated that coefficient stability can be maintained over a given time period at various engagement cycles of the friction clutch by varying the lube flow rate. As is known, the heat removal rate is dependent upon lubricating fluid flow rate and condition of the lubricating fluid.
Traditional lubricating/cooling systems include a shaft-driven pump that delivers lubricating fluid to the clutch pack. The shaft-driven pump is typically a unidirectional pump that provides no lubricating fluid flow when the vehicle is operating in a reverse mode, even though torque requests may still occur. For instance, the vehicle may be subjected to backing up on dirt, gravel or a snow-packed hill when torque transfer during four-wheel/all-wheel drive operation is needed. Additionally, the shaft-driven pump is always driven whenever the vehicle is in forward motion. In many cases, however, lubricating fluid is not required until heat is actually generated on the friction clutch components during, for instances, clutch plate slip conditions. Because the shaft-driven pump is always pumping, inefficiencies are realized and fuel economy can be negatively impacted.
Further, most high thermal loading events of the friction clutch occur at lower vehicle speeds. Therefore, the pump capacity of traditional lubricating systems is typically increased for the sake of being able to deliver more lubricating fluid to the friction clutch at low shaft speeds. Increasing pump capacity may further increase the negative impact on fuel economy, as well as creating potential for pump cavitation at higher shaft speeds. Thus, the need exists to develop improved lubrication/cooling systems for use in power transfer devices which overcome the shortcomings of conventional shaft-driven lubrication pumps.

Power transfer devices with on-demand lubrication systems


A method to increase the capacity efficiency of span-restorable mesh networking on sparse facility graphs. The new approach views the network as a “meta-mesh of chain sub-networks”. This makes the prospect of WDM mesh networking more economically viable than with previous mesh-based design where the average nodal degree is low. The meta-mesh graph is a homeomorphism of the complete network in which edges are either direct spans or chains of degree-2 nodes. The main advantage is that loop-back type spare capacity is provided only for the working demands that originate or terminate in a chain, not for the entire flow that crosses chains. The latter “express” flows are entirely mesh-protected within the meta-mesh graph which is of higher average degree and hence efficiency for mesh restoration, than the network as a whole. Nodal equipment savings also arise from the grooming of express lightpaths onto the logical chain-bypass span. Only the meta-mesh nodes need optical cross-connect functionality. Other sites use OADMs and/or glassthroughs. The resultant designs comprise a special class of restorable network that is intermediate between pure span restoration and path restoration. Most of the efficiency of path restoration is achieved, but with a span restoration mechanism which is more localized and potentially faster and simpler than path restoration. The concept lends itself to implementation with OADMs having a passive waveband pass-through feature to support the logical chain bypass spans for express lightpaths.

Developments in DWDM-based switching technology are giving rise to networking elements that are capable of manipulating individual lightwave carriers or wavebands in ways that are logically similar to SONET-era add-drop multiplexers and cross-connects in terms of the agility they provide for reconfiguration of the transport layer. Like SONET elements that add-drop or cross-connect individual STS-1 or STS-n tributaries, Optical ADMs (OADMs) and Optical cross-connects (OCX) can add/drop or cross-connect wavelengths (or wavebands) [1]. All references in square brackets are listed at the end of the disclosure. One advantage of these DWDM networking elements is that they provide the reconfigurability to adapt the logical wavelength connectivity layer to match changing demand patterns in the service layers enabling the concept of an "automatically switched" (a.k.a "self-organizing") transport network (ASTN) [2], [3]. But another advantage is that OADM and OCX elements enable mesh restoration schemes for the optical networking layer.
One driver for optical layer mesh restoration over the ring protection schemes of Sonet is the greater capacity efficiency that can be achieved [11]-[24]. Mesh networking allows routing of the working demands over shortest paths of the facilities graph and greater efficiency in the sharing of spare capacity for restoration. In practice, however, some real networks are so sparse in their facility-route topology that it may still be hard for mesh-based restoration to prove-in over a ring-based solution which is less capacity efficient but is based on less-costly OADMs rather than OCX. The emphasis on "low-connectivity" graphs reflects the reality of several North American Inter-exchange carrier (IXC) networks. While European networks often have d>4, (see for example the networks in [10], [12]), North American IXC networks can be extremely sparse, with d as low as 2.2 (see for example [6]). d is the average number of separate facility routes leaving each node.
In a bi-connected network with d only slightly above two there will be a preponderance of degree-2 locations and will tend to contain chain sub-networks, like beads of a string. FIG. 1 is a conceptual example of such a sparse facility topology. The example is illustrative only, but to varying extents is characteristic of the North American portions of the networks described at [4] through [10]. At least empirically it is well recognized that North American networks, especially in Canada and over large parts of the mid-U.S.A., tend to be of lower degree than European networks. This is perhaps because, per-unit of geographical area, there have been fewer revenue producing source/sink centers in these regions to justify the historical development of a richer fabric of direct facility routes at the continental scale. And more recently, advances in transmission capacity, and related economy-of-scale in capacity-cost effects, only serve to reinforce the tendency towards sparse facility graphs [25]. With large amounts of capacity and economy of scale it can often be economic to route longer distances, over sparser graphs, rather than seek additional facility routes, at least as a short-term recourse to meeting demand. There is thus a practical reason to be interested in transport network research that is especially focussed on sparse transport graphs. The extent to which ring-based networks have been deployed at the IXC level in North America compared to Europe, is in a sense also a recognition of this sparseness in that rings are easily mapped onto these natural chains. However, rings have to be closed to operate, whereas a set of chain sub-networks may, as proposed herein, be operated at a higher (a meta- level) as a form of mesh-restorable network.
On the other hand, a very sparse graph can make the economic advantage of mesh-based networking questionable. For a few years now informal appraisals have often judged that a network as sparse as in FIG. 1 would be simply too low-degree to benefit enough from mesh restoration (relative to a ring-based status quo). After all, mesh efficiencies can only possibly occur at nodes with d=3 or higher: a d=1 node is not restorable and a d=2 node is already as well served by a shared-protection (BLSR type) ring as it can be. And increasing d by simply acquiring more rights-of-way is generally a most long-term and expensive proposition. Right-of-way costs can be one of the single largest investments the network operator faces involving years of legal work to piece together individual purchases, leases, municipal approvals, permits, and so on, to establish one new edge in the facilities graph. An object of this invention, therefore, is to enhance the efficiency of span-restorable mesh networks on low-degree topologies.
Definitions
The most common practical aim in the design of survivable transport networks is to achieve 100% restorability against any single span failure either through network protection or restoration using a designed-in allocation of spare capacity. We use the term spare to denote any such designed-in reserve capacity whether technically for protection or restoration. Generally protection is used for schemes where the spare capacity is reserved and dedicated to cover a specific set of failure scenarios such as in 1+1 diverse-routed protection, or path- or line-switched rings. Restoration refers to arrangements where a network-wide allocation of spare capacity is not dedicated to any specific failure but is configured as needed to restore affected carrier signals as failures arise. Restoration schemes can generally achieve higher sharing of spare capacity than a corresponding protection scheme, but may require a more complex real-time process for the failure recovery.
Designing for 100% restorability means that all of the failed working demand units, in this case traffic-bearing lightwave links forming parts of end-to-end lightpaths, can be restored by replacement paths either end-to-end across the network or through detour-like path segments formed between the end-nodes of the failed span itself. The required replacement paths must be feasible for every single-failure scenario within the environment of spare wavelengths surviving after the failure. An obvious aim in designing any survivable mesh network is therefore to assure that all such restoration path-sets are feasible within a globally minimized total amount of spare capacity. Every span in a mesh-restorable network has a number of working capacity units and a designed-in number of spare-capacity units. In DWDM networking the units of both working and spare capacity are individual DWDM carrier wavelengths. The spare capacity on a span is not, however, for restoration of demands crossing the same span, but is for shared use in restoration routing for other span failures. Spare capacity is in every way identical to working capacity but it bears no actual traffic (or any such traffic is preemptible) when in the standby state. Each spare wavelength is also fully ready for use but is not yet cross-connected into any lightpath in the non-failure state.
The term span as used here has its origin in the transmission networking community to refer to a grouping of physical layer carrier signals between adjacent cross-connecting nodes that can undergo a common-cause failure. As Bhandari [13] explains " . . . spans are the set of physical transmission fibers/cables in the physical facility graph. Links of the logical connectivity graph are built from spans. A given span can thus be common to a number of links." A span is further defined by us as constituting the set of all the physical working and spare channels that terminate on adjacent cross-connecting nodes and share a common exposure to a single physical cut of their infrastructure, such as a duct or cable. Each working capacity unit on a span is thus part of a logical link in a client service-layer network, all such links being destined to fail together if the corresponding physical span fails. A span is thus like the more recent concept of shared link risk group (SLRG). One physical entity failure may also produce one or more simultaneous span cuts if more than one cross-connect adjacency is involved. Notwithstanding the specific meaning of span here, readers are advised that the more generic term link is often also used in this context. The intended meaning of link as either a service-layer or physical-layer entity has to be construed appropriately in each case.
Reversion is the process of returning affected demand flows back to their pre-failure routes from their restoration routes after physical repair of the failed span. In all cases which follow, other than with dedicated 1+1 APS protection, we are designing capacity for networks in which reversion is assumed to occur following a failure and its subsequent repair before there is any significant probability of a second failure onset. Mesh-restorable networks can be designed to sustain a second span failure while repair of the first failure is ongoing but the spare capacity penalty can be very high [14] and this is not generally the aim in the practical design of transport networks. It is, however, assumed that in networks where spare capacity is available for either restoration or new service provisioning, ongoing provisioning of new service paths during the restored state will have to be cognizant of the spare capacity used by the restoration process and provision new service paths accordingly. An alternative, however, is to operate a transport network with an envelope of working capacity, within which self-organizing ASTN-type service provisioning is conducted with a separate allocation of spare capacity for assured restoration of any single span failure within the working envelope. When it is the working envelope itself that is protected, ASTN operations can remain blind to the details of the failure and restoration reconfiguration.
The generic term demand refers to a working unit of aggregated traffic to be transported between origin-destination (O-D) nodes of the network. The term follows Wu's distinction between traffic itself and the demand units [15] required to transport it. Traffic for example is the individual IP packet and or STS-level tributary flows exchanged between O-D pairs. But demand expresses the aggregate requirement of all traffic types for lightpaths between a given O-D pair. One unit of demand consumes one working wavelength on each span traversed on the route of the demand between O and D.
Loop-Back in Restoration Schemes
The simplest form of network protection is diverse-routed 1+1 automatic protection switching (APS) with a dedicated span- (or node-) disjoint protection (DP) path. 1+1 DP APS uses simple terminals but requires over 100% redundancy in terms of total wavelength-kms required. By the redundancy of a span or a network as a whole, we mean the ratio of total spare to total working capacity. Optical path-protection rings (OPPR) and Optical shared protection rings (OSPR) [16] are the WDM-based counterparts to SONET UPSR and BLSR. The OPPR/UPSR structure is a logical collection of tributary-level 1+1 DP setups that is no more architecturally efficient than 1+1 APS, but is economically efficient because of the economy of scale in sharing of the optical line transmission capacity, and because of the relative simplicity of the OADM terminals. The OPSR/BLSR structure is more efficient than 1+1 DP APS or OPPR/UPSR because it uses a line-level loop-back mechanism, allowing sharing of protection capacity over all spans of the same ring. However, the best an OPSR/BLSR ring can do is achieve 100% redundancy because the protection capacity around the entire ring must meet the largest cross-section of working capacity anywhere in the ring.
This 100% matching of spare capacity to largest-working capacity is a general property of any degree-2 sub-network such as a ring or a chain of degree-2 nodes. A ring is just a sub-network of degree-2 nodal elements arranged in a cycle on the graph, while a chain is a connected segment of degree-2 nodes that does not close on itself. Loop-back refers to the mechanism and the spare capacity requirements required for restoration routing in either a BLSR ring, or in a chain under span restoration. The main point to observe is that at any degree-2 site the spare capacity on the "East" side of the node must meet or exceed the working capacity on the "West" side of the same node, and vice-versa. The topology of a ring or chain dictates that to escape from a cut on one-side of a node, the spare capacity on the other side must be sufficient to support loop-back of the failed working capacity on the cut side.
Mesh Restoration and Protection Schemes
Span restoration is the mesh technology equivalent to OPSR and BLSR rings in that restoration occurs by rerouting between the immediate end nodes of the break. Span restoration is like deploying a set of detours around the specific break in a road that disrupts working paths. Unlike rings, however, mesh span restoration need not be via a single route, nor via simple two-hop routes only. By analogy, if a highway has several lanes, there may be an independent detour path deployed for each lane limited by a hop or distance limit, H, which can be considerably more than two hops. The basic re-routing and capacity design methods for span restoration can incorporate a hop or distance limit and/or an optical path loss limit. Setting the hop or distance limit allows a trade-off between the maximum length of restoration paths and the total spare capacity. As H is increased, more sharing-efficient patterns of re-routing are permitted until at a threshold hop limit H*, the theoretical minimum of spare capacity is reached [20].
For comparisons of the restoration system of the present invention to existing schemes, we consider two variants of the span restoration capacity design problem. In the Spare Capacity Assignment (SCA) problem we consider span-restorable networks in which demands are first shortest-path routed followed by optimal spare capacity assignment for 100% restorability. The total spare capacity is minimized independently of working capacity. In Joint Capacity Assignment (JCA) we consider span-restorable networks where the routing of working paths (and hence working capacity) is jointly optimized with spare capacity assignment to minimize total capacity. Self-organizing methods for this type of restoration, including distributed self-planning, are well developed from work in the 1990s [17], [18], and [32]. Although phrased in the language of the times, i.e., SONET, these schemes are fairly easily mapped into DWDM implementations between opto-electronic cross-connects, especially if digital wrapper [36] is implemented. Alternately, centralized control or OSPF-type path finding may be iterated to develop a set of k-shortest replacement paths for this type of restoration.
Shared backup path-protection and path-restorable networks are also considered here. In Shared Backup Path Protection (SBPP) we assume the shortest route is used for the working path and a single fully-disjoint route is selected for the backup path under optimization to permit sharing of spare capacity over all backup paths whose working paths are failure-disjoint. Demands on working paths that follow physically disjoint routes over the network will not need the restoration capacity simultaneously, hence restoration capacity sharing is permitted. This is logically the same scheme as was proposed for ATM Backup VP restoration [30] in the special case where the maximum permissible over-subscription factor [23] is limited to 1.0. The SBPP approach is receiving much attention in recent IETF deliberations [31]. SBPP is sometimes called failure-independent path protection because the route of the backup path is the same regardless of where a failure arises on the corresponding working path. This is argued to simplify activation and speed up cross-connection of the backup path. But it foregoes the opportunity in capacity planning to re-use the surviving "stub" portions of the failed path either for the same working demand or for restoration of any other demands that underwent simultaneous failure in the corresponding span cut.
In a path-restorable mesh network [21]-[22] demands affected by a span failure are restored simultaneously on an end-to-end basis for each O-D pair affected. This is done in a globally optimized manner that considers the specific failure and can exploit surviving stub capacity from failed working paths using stub release [22]. In a path-restorable network the total spare capacity is strictly sufficient only to support a multi-commodity maximum-flow (MCMF) type of simultaneous re-routing of all affected O-D pairs [32]. In its most capacity-efficient form this involves stub release in which the surviving working capacity units of failed paths are considered available as spare capacity for the particular restoration event. The automatic propagation of an Alarm Indication Signal (AIS) in a digital wrapper is a simple and fast means to effect stub release. The main difference relative to SBPP is that there is no single predetermined restoration route for each working path. Rather a collectively optimized re-routing of all failed paths will occur end-to-end in the presence of the specific failure, the surviving spare capacity following that failure, and the environment of stub release capacity. The path restorable designs we consider are non-joint in the same sense as above in that demands are first routed via their shortest paths before spare capacity is optimized. Further elaboration on the concept of stub release in path restoration is available in [21]-[23]. It has also been found in [21]-[23] that joint optimization adds little further efficiency to a path-restorable design so we consider the simpler non-joint case for comparison to the performance of the present invention.
Conventional Design of Span-Restorable Mesh Networks
The design of span-restorable mesh networks is most often approached using an arc-path Integer Linear Programming (IP) formulation introduced for SCA [20]. As our benchmark here we will use an extension of the model in [20] to include joint optimization of the working path routing (i.e. JCA)[25]. We define JCA as follows:
SSet of spans in the networkPiSet of eligible routes for restoration of span iDSet of O-D pairs with non-zero demanddrNumber of demand units for O-D pair rQrSet of eligible working routes available for demand pair rζjr,q1 if qth eligible route for working demands between O-D pair ruses span j, zero otherwiseδi,jp1 if pth eligible route for restoration of span i uses span j,zero otherwiseCj/lCost of a unit-distance of unit-capacity on span jLjLength of span jƒipRestoration flow assigned to pth eligible restoration route for span iSjNumber of spare capacity units placed on span jgr,qWorking capacity assigned to the qth eligible working route fordemand pair rWjNumber of working capacity units on span j
                                              JCA                                :                                                                        Minimize                                              ∑                              j                ∈                S                                                                                C                jil                            ·                              L                j                            ·                              (                                                      w                    j                                    +                                      s                    j                                                  )                                                                                (        1        )                                                          Subject                                                              to                                :                                                                                ∑                                      q              ∈                              Q                r                                                                    g                          r              ,              q                                      =                  d          r                                                              ∀                      r            ∈            D                                              (        2        )                                                                                ∑                                      r              ∈              D                                                                    ∑                              q                ∈                                  Q                  r                                                                                ζ                j                                  r                  ,                  q                                            ·                              g                                  r                  ,                  q                                                                    =                  w          j                                                              ∀                      j            ∈            S                                              (        3        )                                                                                ∑                                      p              ∈                              P                i                                                                    f            i            p                          =                  w          1                                                              ∀                      i            ∈            S                                              (        4        )                                                                                s            j                    ≥                                    ∑                              p                ∈                                  P                  i                                                                                δ                                  i                  ,                  j                                p                            ·                              f                i                p                                                                                ∀                                    (                              i                ,                j                            )                        ∈                                          S                ×                S                                                  :                                                                                i                            ≠              j                                                          (        5        )
The objective function minimizes the total cost of capacity placed on all spans in the network. Constraints (2) ensure that all working demands are routed. Constraints (3) generate the required working capacity on each span j to satisfy the sum of all (pre-failure) working demands routed over it. Constraints (4) ensure that restoration for failure of span i meets the target level of 100%. Constraint set (5) forces sufficient spare capacity on each span j such that the sum of the restoration paths routed over that span is met for failure of any span i. The largest simultaneously imposed set of restoration paths effectively sets the sj value on each span in the solution. To implement this type of formulation, one needs a pre-processing step to enumerate the sets of eligible working and restoration routes.

Design of a meta-mesh of chain sub-networks


An active shield magnet has a plurality of screening coils which each have a small number of turns in comparison with the number of turns of the main magnet coil assemblies and which are connected in series in a closed loop to reduce the effect of disturbing influences in a working volume of the magnet.

An active-shield assembly is one in which an inner coil system and an outer coil system are connected in series to create magnetic fields in opposing directions so that a strong uniform magnetic field is created at the centre of the coil systems but the stray field prevailing outside the coil systems is very small.
Such an assembly is described in U.S. Pat. No. 4,587,504 issued on U.S. Ser. No. 669,311 filed Nov. 7, 1984, the contents of which are incorporated herein by reference. In the assembly described in U.S. Pat. No. 4,587,504, the coil systems creating the opposing magnetic fields are wound from superconducting wire. Superconducting coil systems are used in order to achieve strength and high precision of the magnetic field created in the centre of the coil systems. A prime application of these magnet assemblies is in NMR (nuclear magnetic resonance) imaging where these qualities are of vital importance.
In order to obtain an image of a subject using NMR techniques a steady background magnetic field is required which is uniform over the region to be imaged (the working volume).
Onto this uniform field are superimposed time-varying gradient magnetic fields which are used to encode position information into the image signal. A superconducting coil system is of particular advantage when the steady magnetic field strength is high, for example more than 0.3T, and the working volume is large, for example a sphere of 0.5 m diameter.
The superconducting condition of the coils is achieved by cooling the coils to very low temperatures, of the order of 4.2 K, using cryogenic techniques. In the superconducting condition, the wires can carry a very high current with negligible energy losses in the wire.
A conventional superconducting coil magnet (that is, a single coil system, without a balancing coil system as in an active shield assembly) has a further quality in that the magnetic disturbances to the magnetic field in the working volume due to external sources of magnetic field, such as other remote coil systems or magnetized objects, are automatically compensated to some degree. This arises from a quality of superconducting coils in that the current in a closed superconducting loop automatically changes in a sense to resist changes in the total magnetic flux threading the loop caused by external disturbing influences. The extent to which the magnetic disturbances are automatically compensated depends on, among other things, the geometry of the magnet and particularly its aspect ratio (the ratio of .sup.d /1 where d is the internal diameter of the magnet and 1 is its length). For a magnet having an aspect ratio of 2 or 3 such as might be used in an imaging application, the effect of an external disturbance is reduced by a factor of about 8 when compared with the field change that would occur if the magnet were absent. The theory underlying this self shielding effect is explained in more detail in U.S. Pat. No. 4,974,113 issued on Ser. No. 168,920 assigned to President and Fellows of Harvard College. This patent also describes arrangements of superconducting screening coils which are intended to reduce even further the effect of external disturbances.
However, a direct consequence of adding the outer coil system to form an active-shield assembly is that this automatic compensation is no longer effective in the working volume. The result is an increase in susceptibility to interference from external disturbing influences in an active-shield assembly as compared with a conventional single superconducting coil magnet. This interference is manifested by a distortion of the images which are produced by the interaction of the background and gradient fields in the working volume.
It is desirable to reduce the effect of disturbing influences on the magnetic field in the working volume of an active-shield assembly. In this regard it is important to consider not only the steady state condition of the assembly in which the current in the superconducting coils is substantially constant but also transient conditions in which the current is varying.
The most relevant of these transient conditions is a "quench" which is the term given for conversion of a coil from a superconducting state to a normal conducting state. A quench may occur unintentionally, due to local disturbances or structural deficiencies or it can be induced intentionally (for example, by means of local electrical heaters) as a way of rapidly reducing the magnetic field. This might be needed for example in a case where it is necessary to give urgent treatment to a patient undergoing an NMR procedure in the magnet assembly. When a quench occurs, there is a rapid increase in resistance in the quenched part of the coil which causes the energy stored in the coil system to be converted into heat. The heat is conducted to adjacent parts of the coil, causing these parts to quench. As an increasingly large part of the coil is quenched, the temperature associated with the heat energy increases, causing the resistance of the coil to rise further and accelerating the quench process until all the stored magnetic energy is converted into heat. This can occur extremely quickly, typically in about 10 to 20 seconds.
As described in U.S. Pat. No. 4,587,504 the coils of an active-shield magnet assembly are designed not only to produce a uniform magnetic field at the centre of the assembly but also to produce an external magnetic field which is as low as possible as close as possible to the assembly. The external magnetic field is termed herein the "stray field" and is commonly specified in terms of an ellipsoidal or cylindrical volume outside which the magnetic field due to the magnet assembly nowhere exceeds a specified level. This provides a way of denoting a safety zone a certain distance from the magnet. Any measures taken to reduce the effect of disturbing influences on the magnetic field in the working volume should preferably not be such as to cause the stray field to exceed its nominal limits, even during a quench.
U.S. Pat. No. 4,974,113 referred to above does not address specific problems associated with active-shield magnets or the difficulties arising during transient conditions.
An attempt to address these problems is proposed in EP-A-0299325 (Siemens) which describes an active-shield magnet in which the inner and outer magnet systems are decoupled by a superconducting current limiter. The current limiter permits slight current differences to exist between the inner and outer coil systems. As a result, magnetic field disturbances within each coil system can be compensated by a current modification. While the theory is sound, there are considerable difficulties in achieving a reliable practical implementation based on this theory. In particular, for magnets of a size and geometry suitable for use in NMR applications, the current limiter must have a limiting current of less than 1 amp yet be able to withstand several hundred volts applied across its end if the stray field is to be maintained within bounds, even during quench conditions. A typical critical current density in a superconductor is about 4000 A per mm.sup.2, so to achieve less than 1 amp it is necessary to use a very fine filament, of the order of 10 .mu.m. Such a filament is both difficult to manufacture and to handle. Moreover, as the ends of the filament are adjacent in the coil as wound, very high insulation is necessary between the ends because of the high voltages which are developed. Thus the problem outlined above remains unsolved at a practical level.


A salt making method comprising putting a crude salt-water mixture (5) comprising crude salt or rock salt and bittern in a vessel (1), blowing the air from a pipe (7) into the mixture (5) with a pump (9), crystallizing the component salt out of the mixture (5), and precipitating the salt as a common salt (S) at the bottom of the vessel (1). The remainder of the mixture (5) is discharged through a filter (13) into a tank (17), where it is stored as a concentrated brine (15), which is then discharged through a filter layer (16) and a drain (18), and crude salt is dissolved therein to recycle as a crude salt-water mixture. The concentrated brine (15) may be used after being mixed with the extracts of aloe, mozuku (Nemacystis decipiens), rice bran, etc. The air may be blown into the mixture (5) under heating.

It is known that common salt is made by depositing sodium chloride from sea water but, recently, natural salt, i.e., salt containing not only sodium chloride but also other sea water components such as minerals, has been attracted attention.
It is said that sea water contains almost the same components as those of human blood and, from this viewpoint, natural salt is considered preferred for human consumption.
As a result, the number of people who use natural salt for food is increasing and "salt application health method" in which a natural salt is applied to a human body and "salt bathing" in which a natural salt is added to bath water have been proposed, not only for health and cosmetic purposes but also as therapeutics of atopic dermatitis and so on.
As a method for making a natural salt, a method is known in which a crude salt, which is a kind of natural salt obtained by evaporating water from sea water by the heat of the sun, is dissolved in water and then heated at a temperature of 140 to 180.degree. C. for 6 to 12 hours.
The above method has the problems that the heating requires a large amount of energy and a large apparatus and the salt becomes unnatural by deviation of the components or removal of bittern, particularly magnesium and calcium.
The present invention, considering the above problems, has the object to provide a salt making method and apparatus which are simple in construction and can make a natural salt.


A high speed, low-to-high voltage CMOS driver circuit has a CMOS output stage, an intermediate voltage translation stage, and an input stage. The input and intermediate stages are designed to generate mutually exclusive control signals which activate the PMOS and NMOS transistors of the output stage. The control signals operably turn "off" the active transistor before turning "on" the inactive transistor. Independent control signals substantially reduce or eliminate crossing current in the output stage to thereby reduce energy power waste.

Semiconductor integrated circuits employ output driver circuits to drive capacitive loads. One example use of an output driver circuit is to drive row select lines in a semiconductor memory array.
Conventional output driver circuits utilize complementary metal-on-semiconductor (CMOS) technology. A conventional CMOS output circuit includes a p-channel MOS (PMOS) transistor coupled between voltage and an output node, and an n-channel MOS (NMOS) transistor coupled between the output node and ground. The CMOS design enables the PMOS transistor to be "on" while the NMOS transistor is "off", and vice versa, in response to a single input signal. When the PMOS transistor is "on" and the NMOS transistor is "off", the CMOS driver circuit outputs a voltage. Conversely, when the PMOS transistor is "off" and the NMOS transistor is "on", the output of the CMOS driver circuit is grounded.
One drawback inherent in the design of conventional CMOS output driver circuits is that during the rail-to-rail voltage swing at the input, there exists a period of time when both the PMOS and NMOS transistors are "on". This dual activation condition causes a phenomenon known as "crossing current" which wastes power.
This invention provides a high speed, low-to-high voltage CMOS driver circuit which eliminates or substantially reduces crossing current in an effort to conserve power.

Low-to-high voltage CMOS driver circuit for driving capacitive loads